seminar bencana alam - ums...kertas kerja/ editorial: dr. ejria saleh publisiti: cik.farrah anis...

SEMINAR BENCANA ALAM 2013

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Perutusan Naib Canselor

Bismillahir Rahmanir Rahim

Assalammualaikum Warahmatullahhi Wabarakatuh dan Salam sejahtera

Syukur ke hadrat Allah S.W.T kerana dengan limpah kurnia-Nya, Seminar Bencana

Alam 2013 dapat dilaksanakan dengan jayanya. Syabas dan tahniah diucapkan di

atas kerjasama antara Unit Kajian Bencana Alam dan Persatuan Geologi Malaysia

serta Jawatankuasa Pelaksana Seminar atas usaha gigih dan dedikasi dalam

memastikan kelancaran seminar ini.

Dengan penganjuran program seumpama ini, pakar-pakar dalam pelbagai

bidang bencana alam dapat menyumbang dan berkongsi hasil penyelidikan,

mewujudkan rangkaian serta mengeratkan hubungan kerjasama di antara satu

sama lain.

Saya berharap agar seminar ini akan mencapai objektif yang disasarkan

bagi menyediakan platform kepada penyelidik untuk membincangkan, berkongsi

serta bertukar idea dan hasil penemuan dalam kajian berkaitan bencana alam.

Adalah menjadi harapan pihak universiti melalui program sebegini, mahasiswa yang

cemerlang dari segi akademik dan sahsiah dapat dilahirkan sejajar dengan Misi

serta Visi Universiti Malaysia Sabah.

Setinggi-tinggi penghargaan dan sekalung budi sekali lagi buat mereka yang

menjayakan seminar ini sama ada secara langsung atau tidak langsung

terutamanya kepada AJK Seminar dan Pusat Pengajian Pascasiswazah atas

kerjasama yang diberikan.

Sekian, terima kasih.

“PENYELIDIKAN DAN INOVASI ASAS KECEMERLANGAN UNIVERSITI”

PROF. DATUK DR. MOHD HARUN BIN ABDULLAH

Naib Canselor

Universiti Malaysia Sabah


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Kata-Kata Aluan Dekan Sekolah Sains & Teknologi

Bismillahir Rahmanir Rahim

Assalammualaikum Warahmatullahhi Wabarakatuh dan Salam sejahtera

Alhamdulillah, syukur ke hadrat Ilahi, maka dengan izin-Nya, Seminar Pascasiswazah

Sekolah Sains dan Teknologi bejaya dianjurkan pada tahun ini dengan kerjasama

Sekolah Sains dan Teknologi dan Pusat Pengajian Pascasiswazah. Dalam

kesempatan ini saya ingin mengucapakan setinggi-tinggi tahniah dan amat

berbangga dengan komitmen yang diberikan oleh para pensyarah dan para

pelajar pascasiswazah.

Seminar ini diharap dapat menyumbang ilmu dan manfaat kepada semua

pihak terutama para pelajar Pascasiswazah Sekolah Sains dan Teknologi. Selain itu

diharapkan hubungan di antara para pelajar Pascasiswazah dengan para

pensyarah dapat dijalinkan. Secara tidak langsung, seminar ini turut manjadi medan

perkongsian ilmu dalam dalam menghasilkan penyelidikan yang bermutu dan

berkualiti.

Seminar ini juga turut menjadi printis kepada penglibatan mahasiswa dalam

menghasilkan penyelidikan yang dapat diterbitkan ke peringkat yang lebih tinggi.

Akhir kata semoga seminar ini akan tetap diteruskan pada masa akan datang untuk

melahirkan graduan pascasiswazah yang inovatif dan proaktif.

Setinggi-tinggi penghargaan dan sekalung budi sekali lagi kepada AJK pelaksana

dan Pusat Pengajian Pascasiswaza atas sumbangan kewangan yang diberikan.

Tidak lupa juga buat mereka yang menjayakan seminar ini sama ada secara

langsung atau tidak langsung.

“BERTEKAD CEMERLANG”

PROF MADYA DR BABA MUSTA

Dekan Sekolah Sains dan Teknologi



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Kata-Kata Aluan Pengerusi BENCANA 2013

Salam sejahtera

Syukur ke hadrat ilahi, maka dengan izin-Nya, Seminar Pascasiswazah Sekolah Sains

dan Teknologi berjaya dianjurkan pada tahun ini. Seminar Pascasiswazah Sekolah

Sains dan Teknologi merupakan program tahunan yang betujuan untuk

mendedahkan para pelajar Pascasiswazah membentang hasil penyelidikan

mereka . Secara tidak langsung seminar ini diharapkan akan menjadi ruang

kepada para pelajar untuk bertukar-tukar ilmu pengetahuan yang sedia ada.

Pada kesempatan ini setinggi penghargaan dan ribuan terima kasih kami

ucapkan kepada Timbalan Naib Canselor (Akademik & Antarabangsa), Dekan

Pusat Pengajian Pascasiswazah dan Dekan Sekolah Sains dan Teknologi atas

kerjasama dan sokongan untuk kelancaran seminar ini.

Terima kasih juga kepada para pensyarah yang terlibat dalam menjayakan

seminar ini di atas nasihat dan bimbingan yang diberikan. Akhirnya tidak lupa juga

kepada Ahli Jawatankuasa Seminar Pascasiswaza yang merupakan nadi pengerak

seminar atas usaha yang tungkus lumus seminar pada tahun ini. Semoga pada

masa akan datang Seminar pascasiswazah akan lebih giat diadakan untuk

mencapai matlamat, misi dan visi sekolah.

Sekian, Terima Kasih.

“BERTEKAD CEMERLANG”

DR. JUSTIN SENTIAN

Pengerusi

Seminar Bencana Alam 2013



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AHLI JAWATANKUASA SEMINAR BENCANA ALAM 2013

Penaung:

Penasihat:

Prof. Dr. Shahril Yusof

(Timb. Naib Canselor, P&I, UMS)

Prof. Madya Dr. Baba Musta

(Dekan Sek. Sains & Teknologi)

Prof. Dr. Felix Tongkul

(Pengarah, Pusat Penyelidikan &

Inovasi)

Prof. Dr. Sanudin Hj. Tahir

Pengerusi: Dr. Justin Sentian

Timb. Pengerusi: Dr. Ismail Abd. Rahim

(Ketua Unit Kajian Bencana Alam)

Setiausaha:

Bendahari:

Pn. Hazerina Pungut

Pn. Hennie Fitria W. Soehady E.

Seketeriat: En. Mohamed Ali Yusof Bin Mohd Husin

Cik Nabila Mohd. Salleh

Cik Rasyidah Moneey

Cik Hazlinda Ibno

Cik Fatimah Sudirman

Jamuan: Pn. Carolyn Melisa Payus

Pengangkutan/

Kebajikan:

En. Ahmad Norazhar Mohd Yatim

En. Ricardo Nic Jially

Teknikal: En. Junaidi Asis

En. Rezal Rahmat

En. Razuan Matthew

En. Azmie

Kertas Kerja/

Editorial:

Dr. Ejria Saleh

Publisiti: Cik.Farrah Anis Fazliatul Adnan

En. Dazvieo Keniin

Protokol: En. Rodeano Roslee

En. Muzafar Zaki


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MAJLIS PERASMIAN SEMINAR BENCANA 2013

03 DISEMBER 2013 (SELASA)

AUDITORIUM PERPUSTAKAAN, UNIVERSITI MALAYSIA SABAH.

8.00 pagi Ketibaan dan Pendaftaran peserta

8.30 pagi Ketibaan tetamu kehormat

8.45 pagi Ketibaan YBhg. Prof. Madya Dr. Baba Musta,

Dekan Sekolah Sains dan Teknologi, UMS

9.00 pagi Bacaan Doa

Ucapan Alu-aluan oleh Pengerusi BENCANA 2013

Dr. Justin Sentian

Ucapan Perasmian oleh Dekan SST, UMS

YBhg. Prof. Madya Dr. Baba Musta

9.30 pagi Penyampaian Cenderahati

9.40 pagi Jamuan


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TENTATIF SEMINAR BENCANA ALAM 2013

HARI PERTAMA 3hb DISEMBER 2013 (SELASA)

0830 – 0900 Pendaftaran Peserta (Auditorium Perpustakaan, UMS)

0900 – 0940 Majlis Perasmian (Auditorium Perpustakaan, UMS)

0940 – 1000 JAMUAN

1000 – 1030 Pembentangan Ucaptama:

Prof. Madya Dr. Phua Mui How

PEMBENTANGAN SIDANG A

Pengerusi Sidang :

Dr. Justin Sentian

Sesi Teknikal Penyampai & Tajuk Skop

1030 – 1050 A-01 Prof. Dr. Felix Tongkul

Kajian Bencana Banjir di kawasan

Pekan Tenom.

Banjir

1050 – 1110 A-02 Nauwal Suki & Mohd Hisbany Mohd

Hashim

Preliminary Studies of Construction

Materials Under Tropical Climate

Effects

Perubahan

Iklim

1110 – 1130 A-03 Nurfarhana Diyana Binti Abdul Hadi &

N.H. Abdul Hamid

Lesson Learnt From Past Earthquake

in Malaysia

Gempabumi

1130 – 1150 A-04 Munirah Binti Ariffi & Subramaniam

Moten

The Impact of Tropical Cyclones in

The Western Pacific Ocean and

South China Sea On The Rainfall In

Malaysia

Ribut Tropika

1150 - 1230 SESI PEMBENTANGAN POSTER

1230 – 1400 Makan Tengahari

PEMBENTANGAN SIDANG B

Pengerusi Sidang :

Dr. Ismail Abdul Rahim

Sesi Teknikal Penyampai & Tajuk Skop

1400 – 1420 B-01 Rodeano Roslee, Tajul Anuar

Jamaluddin & Norbert Simon

Urban Geology in Sabah, Malysia

Geologi

Sekitaran

1420 – 1440 B-02 Shamilah Anudai @ Anuar, N.H. Abdul

Hamid & Md. Salleh

Seismic Performance of 3-Storey

Tunnel Form System Building With

Double Units Subjected To Lateral

Cyclic Loading

Gempabumi

1440 – 1500 B-03 Prof. Dr. Wan Mohd. Norsani Wan Nik

Review of Coastline Changes Due To

Erosion at Pantai UMT

Hakisan

Pantai &

Sungai


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1500 - 1520 B-04 Bala Raju Nikku

1520 – 1540 JAMUAN

1540 – 1600 B-05 Yap Siew Fah

Floods, What Can We Do?

Banjir

1600 – 1620 B-06 Farah Alwani Binti Wan Chik F, T.A.

Majid , S.N.Che Deraman & M.K.A.

Muhammad

An Overview of Windstorm

Phenomenon In Penang State of

Malaysia

Ribut Tropika

1620 – 1640 B-07 Hj Ajak Bin Hj Awang

1640 - 1700 MAJLIS PENUTUPAN

TAMAT HARI PERTAMA

HARI KEDUA 4hb DISEMBER 2013 (RABU)

0900 – 1200 Pameran Poster

SEMINAR TAMAT

SESI POSTER

No. Poster Penyampai & Tajuk Skop

C-01 Norbert Simon, Rodeano Roslee, Nightingle Lian Marto,

Juhari Mat Akhir, Abdul Ghani Rafek & Goh Thian Lai

Lineaments and Their Association with Landslide

Occurrences Along The Ranau – Tambunan Road,

Sabah.

Tanah

Runtuh

C-02 Nurul Adyani Ghazali, Nor Azam Ramli, Ahmad Shukri

Yahaya

Application of Probability Distribution of Predict

Particulate Matter (PM10) Concentration In Malaysia

Perubahan

Iklim

C-03 Mohamed Ali Yusof Bin Mohd Husin & Baba Musta

Effects Of Moisture On The Strength Of Crocker

Formation Soil Along Kota Belud – Ranau Road,

Tamparuli, Sabah.

Tanah

Runtuh

C-04 Dr. Ismail Abd Rahim

The Stability Of Temburung Formation In Beaufort Area,

Sabah

Tanah

Runtuh

C-05

C-06

C-07

C-08

C-09

C-10


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ABSTRAK


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A-01

KAJIAN GEOMORFOLOGI BENCANA BANJIR DI DAERAH TENOM, SABAH

Wong Fui Peng & F. Tongkul

Unit Kajian Bencana Alam

Sekolah Sains Dan Teknologi, Universiti Malaysia Sabah

ABSTRAK. Daerah Tenom yang terletak di lembangan Sungai Pegalan dan Sungai

Padas merupakan kawasan yang sering dilanda banjir. Misalnya pada tahun 2009

kejadian banjir yang paling teruk dialami dimana sesetengah kawasan telah

mengalami banjir lebih dari dua meter dan menyebabkan bahaya kepada orang

awam dan kerugian harta benda. Pelbagai usaha telah dilakukan oleh Kerajaan

melalui Jabatan Pengairan dan Saliran untuk mengurangkan masalah ini seperti

penambahbaikan sistem perparitan, pendalaman sungai dan pelurusan sungai,

namun banjir terus berlaku. Untuk mengetahui keseriusan banjir di daerah ini satu

kajian geomorfologi telah dilakukan untuk mengenalpasti taburan kawasan yang

mengalami banjir dan berpotensi untuk banjir, khususnya di sekitar Pekan Tenom.

Untuk kajian ini DTM (IFSAR) oleh Intermap telah digunakan untuk menganalisis

bentuk permukaan bumi. Perisian Global Mapper digunakan untuk mengenalpasti

keluasan kawasan banjir pada ketinggian tertentu dan perisian GIS digunakan

untuk memetakan taburan banjir. Hasil kajian mendapati kawasan yang boleh

dilanda banjir yang berada pada ketinggian dari 174-180 meter mempunyai

keluasan sekitar 3014 hektar. Bahagian barat Sungai Padas yang mempunyai

topografi rendah, adalah yang paling mudah banjir. Walau bagaimanapun

keluasan banjir disini adalah kecil kerana terdapat banyak bukit kecil. Kawasan

yang terletak di bahagian timur Sungai Padas mempunyai keluasan banjir yang

paling besar sebab topografinya agar rata. Kawasan yang berpotensi dilanda

banjir yang berada pada ketinggian 180-181 meter mempunyai keluasan sekitar 364

hektar. Kawasan ini sebahagian besar terletak di utara kawasan kajian, terutama

disebelah timur Sungai Pegalan. Secara umumnya, banjir lebih mudah berlaku di

kawasan sekitar Sungai Padas berbanding dengan Sungai Pegalan kerana ia

mempunyai ketinggian topografi yang lebih rendah.

KATA KUNCI. Sungai Pegalan, Sungai Padas, Topografi, Keluasan banjir, Kawasan

senang banjir.


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A-02

PRELIMINARY STUDIES OF CONSTRUCTION MATERIALS UNDER TROPICAL CLIMATE

EFFECTS

Nauwal Suki1 & Mohd Hisbany Mohd Hashim2

1,2Faculty of Civil Engineering, Universiti Teknologi MARA,

Shah Alam, Selangor, Malaysia

ABSTRACT. Concrete and steel combination has been used in the construction

industry for years and it is undeniable that it has successfully constructed various

structures. However, tropical climate effects such as the sun rays, chemicals from the

rain or other particles that might be brought by the wind causes corrosion and thus

may affected the structures. This study was done in order to know the extent of

durability of concrete and steel under the harsh tropical climate effects and the

results shall prepare us for the problems that may arise. Through this study, seven

concrete cubes of grade 30 were cast and then cured for different numbers of days.

The cubes are cured for 7, 14 and 28 days. The cubes were then divided and placed

in two different areas; one is an area which has a room temperature surrounding

while the other is exposed to the tropical climate. These cubes were placed there

along with steel for a period of three and six months. Once the exposure time has

lapsed, two tests were done to test the mechanical properties of both construction

materials. Concrete had undergone compression test while steel had undergone

tensile test. After the tests were done, it was shown that the materials which were

placed in room temperature surrounding are more durable and stronger as

compared to its counterpart which were placed in the exposed areas.

KEYWORDS. Preliminary studies, Construction materials, Tropical climate.


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A-03

LESSON LEARNT FROM PAST EARTHQUAKES IN MALAYSIA

N.D Abdul Hadi1, N.H Abdul Hamid2

1PhD Candidate, 2Assoc. Prof., PhD,

Faculty of Civil Engineering,

Universiti Teknologi MARA,

40450 Shah Alam,

Selangor, Malaysia.

[email protected]

ABSTRACT. This objective of this article is to find the effect of past earthquakes in

Malaysia, and presents a proposed procedure to avoid damages in building caused

by low to moderate earthquake. This research includes findings on potential seismic

sources from Malaysia and neighboring countries and effect of earthquakes to

present structures in Malaysia. A comparative study was done on seismic hazard in

Malaysia from the Sumatran fault. The 2004 Aceh earthquake and 2009 Sumatra

Earthquake are two of the most strong and distant earthquake that has affected

Malaysia. The level of damages on tall buildings in Malaysia following the

earthquakes was found to be predictable at a distance as far as 350km from

potential earthquake sources. Residents in Malaysia, mainly in Selangor and Penang

felt the earthquake and some reported the high intensity of the earthquake caused

cracks on the building. Cracks in structural member indicate a vulnerable structure

especially cracks in column where a diagonal shear crack tends to form. In order to

prevent the formation of cracks, a suitable seismic design code of practice should

be adapted. It is advisable for Malaysia to adapt Eurocode 8 code of practice in

order to avoid further damage of buildings should high intensity earthquake occurs

in Malaysia.


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A-04

THE IMPACT OF TROPICAL CYCLONES IN THE WESTERN PACIFIC OCEAN AND SOUTH

CHINA SEA ON THE RAINFALL IN MALAYSIA

Munirah Binti Ariffin & Subramaniam Moten

Research Section, Malaysian Meteorological Department,

Jalan Sultan, 46667 Petaling Jaya, Selangor, MALAYSIA.

ABSTRACT. Tropical cyclones (TCs) are intense synoptic systems that significantly

modifies the basic atmospheric state through the entire troposphere. This has a

strong influence on the regional rainfall pattern, even to countries that are not

directly on the path of these cyclones. The Malaysian region is in close proximity to

one of the most active cyclogenesis region in the world, that is the west north

Pacific (WNP) and the South China Sea (SCS) region. This region has the highest

number of TCs globally with an average of 27 cyclones per year, with nearly half of

them reaching typhoon intensity. In this study 57 years of TC data from the Regional

Specialized Meteorological Centre (RSMC) - Tokyo and rainfall data for the same

period from selected principal meteorological stations in Malaysia is used to study

the impact of TCs on the rainfall in three Malaysian regions; Sabah, Sarawak and

northwestern Peninsular Malaysia. The probability of rainfall at different stages of the

cyclone and their location in the WNP and SCS reveals that the rainfall has a higher

probability of occurrence when the cyclone is in the open sea, whereas over

northwest Peninsular Malaysia it is during landfall or close to the Indochina coast the

probability is higher. When the TCs are in the SCS, Sarawak has a higher chance of

getting rain than when the TCs are in WNP. Though the chance of receiving rain

when TCs are located in WNP or SCS is more than 70 percent, but there is less than

40 percent chance of getting heavy rain (>10mm). For Sarawak and northwestern

Peninsular Malaysia when the TCs are located in the SCS, the chance of rain

increases as the TC category increases from depression to typhoon stage. For

Sabah when the TCs are located in WNP, the probability of rain is higher when the

TCs are at the tropical storm stage as compared to other stages.

KEYWORDS. Tropical cyclone, cyclone intensity, rainfall distribution and rainfall

probability.


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B-01

URBAN GEOLOGY IN SABAH, MALAYSIA

Rodeano Roslee*1, Tajul Anuar Jamaluddin2, S. Abd Kadir S. Omang1 & Norbert

Simon2

1 Program Geologi, Sekolah Sains dan Teknologi, Universiti Malaysia Sabah,

Jalan UMS, 88400 Kota Kinabalu, Sabah

2 Program Geologi, Fakulti Sains dan Teknologi,

Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor

*Email address: [email protected]

ABSTRACT. Urban geology is the study or application of the interaction of human

and natural processes with the geological environment in urbanised areas. Rapid

urbanization in developing countries like Malaysia is directly related to deterioration

of the geo-, eco-systems. It is, therefore, urgent to understand the urban geosystem

and generate the data and awareness amongst planners and/or researchers to

produce long ranging, sustainable and disaster-proof growth. The current status of

work in urban geology area is mainly focused at estimating the levels of pollution,

land use planning, disaster management and other remedial measures apart from

the greater thrust on urban hydrology. In the absence of geological factors, several

studies on urban environments may remain two dimensional, and the urban

development as short sited. Ignorance on sustainable and wise utilization of the

natural resource system made some towns in Sabah, Malaysia quite vulnerable,

affecting physical and mental health of the society. How these factors are

concerned to geology; and the ways the knowledge of geology can help to solve

some of these problems should be of great concern to Urban Geologist. Natural and

human factors have contributed to the occurrence of environmental and

engineering geological problems in Sabah, Malaysia. These include landslides and

slope instability, gullying, building damage, river and coastal erosions, informal

settlements, groundwater quality, industrial pollution, inappropriate solid waste

management, etc (Fig. 1). Besides shaking incident low intensity earthquake results

also provide an opportunity to follow up geological disasters (Fig. 2). The identified

urban geology problems in Sabah, Malaysia require immediate solutions in order to

make the state sustainable. The collection of detailed geological information and

monitoring data, including the engineering geological characteristics of soils,

hydrogeological conditions, slope instability, hydrogeological characteristics,

groundwater quality etc, will serve to increase awareness of the geological impact

on urban development. It is believed that an understanding of these problems will

mailto:[email protected]


14

help decision makers or planners devise effective urban policies and land-use

planning strategies. Therefore here is a need to integrate and discuss all these

aspects under single roof of urban geology.

KEYWORDS. Urban Geology, Geo-disaster, Environmental Geology and Sabah.

Figure 1. Some examples of geological disasters ever to occur in Sabah, Malaysia.

Figure 2. Position number epicenter earthquake along the coast of Sabah and the

surrounding which can generate the geological disasters events (Sources from USGS

and JMS (Sabah)).

Kg. Kiau’s landslide (09/05/2012) Land subsidence at Taman Landmark Hagibis Storms (28/11/2007)

Beaufort flood (15/03/2009) Forest burning at Telupid area Kunak earthquake (2008)


15

B-02

SEISMIC PERFORMANCE OF 3-STOREY TUNNEL FORM SYSTEM BUILDING WITH DOUBLE

UNITS SUBJECTED TO LATERAL CYCLIC LOADING

A. A Shamilah, N. H Abdul Hamid & S. M.D Salleh

Faculty of Civil Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor,

Malaysia.

Email : [email protected]

ABSTRACT. A one-third scale of double unit 3-storey reinforced concrete tunnel form

building (TFB) is investigated. A set of 3-storey reinforced building together with

foundation beam are designed, constructed and tested under quasi-static

reversible in-plane lateral cyclic loading. This building is tested from ±0.01% drift until

±1.0% drift with an increment of 0.25% drift. The shear wall of tunnel form system

started to crack at -0.25% (pulling) drift on wall-slab (wall 1) connection of the first

floor. More cracks occurred as the increment of drift on wall surface and the

connection. The diagonal crack found to form at +1.25% drift on the first and second

floor outer wall 3. The diagonal crack also occurred on the second floor of the outer

wall 1. The maximum in-plane lateral loading recorded for this specimen was

71.84KN at +1.0% drift. The ductility of TFB obtained from this experiment result is μ =

4.8 which is still in the range 3 to 6. This showed that TFB performed well under long

distant earthquake for minor to moderate.

KEYWORDS. Tunnel form building system, lateral strength, ductility, stiffness,

equivalent viscous


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B-03

REVIEW OF COASTLINE CHANGES DUE TO EROSION AT PANTAI UMT

W.B. Wan Nik

Department of Maritime Technology, Faculty of Maritime Studies and Marine

Science, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu

ABSTRACT. Marine ecosystem includes the area at the shoreline is the area which

sensitively reacts with any changes occur around it. The changes might affects

either temporarily or permanently. These changes include alteration in morphology,

beach profile and contour. Coastal development creates hazard which affects the

natural environment such as erosion. Reclamation of sand to form a runway for

Sultan Mahmud Airport is an example of coastal erosion due to man-made product.

The aim of this study is to evaluate the changes of the beach near Universiti Malaysia

Terengganu (UMT). This study also provides a few ways to overcome the problem.

The study area was set from Sultan Mahmud Airport to Pantai Mengabang Gelam

which covers the coastline area of 3.4 kilometres. Visual observation was done to the

studied area to see the changes of coastline. It was found that the development of

the runway for Sultan Mahmud Airport has caused severe erosion along this studied

area. There is structural damage along this shoreline and the devastation has

affected socio economy of surrounding resident. This paper reports the erosion

process occurs along the coastline of Tok Jembal and UMT and the method applied

to overcome erosion.

KEYWORDS. erosion, coastal development, rock revetment


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B-04


18

B-05

FLOODS

WHAT CAN WE DO?

Yap Siew Fah

Department of Irrigation and Drainage Sabah

ABSTRACT: According to the Oxford Dictionary of Current English, flood is the

overflowing or influx of water, especially over land or simple inundation. To the

author, flood is “too much water in the wrong place at the wrong time or that

human are in the wrong place at the wrong time”. As flood can threaten life and/or

property, it is important that these concerns are addressed. This paper highlights the

four basic ways to reduce the threats and their respective merits and constraints.

The four basic ways are the modification of human behavior, modification of the

behavior of flood, modification of properties and living with floods. A few technical

terminologies that are commonly related to flood such as flood frequency,

floodway, flood fringe, flood storage, and flood hazard are included to create a

better understanding of flood and adaptation to flood.


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B-06

AN OVERVIEW OF WINDSTORM PHENOMENON IN PENANG STATE OF MALAYSIA

F.A. Wan Chik*, T.A. Majid1,2,

S.N.Che Deraman2, M.K.A. Muhammad2

1Disaster Research Nexus, Engineering Campus, Universiti Sains Malaysia 14300

Nibong Tebal, Penang, Malaysia

2School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, 14300

Nibong Tebal,Penang, Malaysia.

ABSTRACT. During monsoon season, heavy rain and windstorm prone occurred in

micro scale and affected east coast of Peninsular Malaysia and East Malaysia. Aim

of this conducted pilot study is to review on the occurrence of strong wind and

house damaged in five districts in Penang. Data was collected in four years period

from 2010 to 2013 for five respective districts in Penang which acquired from Land

and District Office, thus, all data were analyzed. Meanwhile, the frequencies of

heavy storm occurrence and number of houses damaged have been obtained.

Data comparison between every district in terms of occurrence in month and year

and number of damages were established from the plotted graph. From the graph,

the highest frequency of windstorm occurrence was found at Northern Penang

(SPU), with 538 cases was reported, and followed by Southern Penang (SPS), with 50

cases, Central Penang (SPT), with 29 cases, South West Penang (BD), with 3 cases

and the lowest occurrence at North East Penang (TL), with 2 cases. The highest

number of houses damaged was hampered in year 2012 at Northern Penang (SPU)

with 243 number of houses, while, the least number of houses damaged occurred in

year 2011at North East Penang (TL) by only one house damage. The trend number of

occurrence and damaged also observed step up yearly due to the climate change

and global warming tendency. The important factor that may contribute to climate

change is urbanization. This study shows that windstorm is a phenomenon and must

be considered in Malaysia. It is important to note that a rise in severe windstorm

events, thus, increase the damages and losses and also human life.

KEYWORDS. Wind storm occurrence, frequencies, number of house damaged.


20

B-07

XXXXXXXXX

Hj. Ajak Hj Awang

XXXXXXXXXX

ABSTRACT.


21

C-01

LINEAMENTS AND THEIR ASSOCIATION WITH LANDSLIDE OCCURRENCES ALONG THE

RANAU-TAMBUNAN ROAD, SABAH

Norbert Simon1*, Rodeano Roslee2, Nightingle Lian Marto3, Juhari Mat Akhir1,

Abdul Ghani Rafek1, Goh Thian Lai1.

1School of Environment and Natural Resources Sciences, Faculty of Science and

Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia.

*e-mail: [email protected]

2 School of Science & Technology, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota

Kinabalu, Sabah, Malaysia

3Minerals and Geoscience Department Malaysia (Sabah), Jalan Penampang,

Locked Bag 2042, 88999 Kota Kinabalu,

Sabah, Malaysia.

ABSTRACT. Lineament can be considered as a leading factor in mountainous

regions. These studies associate lineaments with landslide occurrences.. To date, no

guidelines exist and depend on the researcher subjectivity. This study proposes a

simple method to assess the influence of lineaments on landslide occurrences based

on the concept of lineament density. The Ranau-Tambunan districts with a 50 km

road stretch from Ranau to Tambunan, crossing the Crocker and Trusmadi

Formations is selected as the study area. In total, the study area is 87.8 km2. Both

formations have similar area with Crocker (42.6 km2) and Trusmadi (43.8 km2) and

the rest are either igneous and alluvium (1.4 km2). The lineaments were identified

using a 5x5 weighted kernel filter on a RADARSAT-1 standard mode image. The

lineament density was calculated using a 1 km x 1 km grid on the lineament map

and the density for each 1 km2 grid is represented by the total length of lineaments

in a grid. A total of 348 lineaments were identified with the lineament density map

classified into three classes of density, resulting low (<318m), moderate (319-775m),

and high (>775m) using the natural break classification. The presence of lineament is

more pronounced in the Trusmadi compared to the Crocker Formation. The

influence of lineament on landslide occurrences was examined by in tersection of

the lineament density map with 75 landslides observed from fieldwork to determine

the number of landslides in each density class. Out of the 75 landslides, 29 landslides

occurred in the Crocker Formation and the other 46 landslides in the Trusmadi

Formation. From the intersection, a total of 47 landslides were captured into the high

density class. The number of landslides recorded in the high density class in the

Crocker and Trusmadi Formations are 20 and 27 respectively. These results indicate

over half of the landslide occurrences are induced by the presence of lineaments

with with the highest located in the Trusmadi Formation. As a conclusion, this study

demonstrates a simple technique for lineament density determination and its

influence on landslides in an area that consist of two different rock formations.

KEYWORDS. Lineament, lineament density, landslides, filter


22

C-02

APPLICATION OF PROBABILITY DISTRIBUTION TO PREDICT PARTICULATE MATTER (PM10)

CONCENTRATION IN MALAYSIA

*Nurul Adyani Ghazali1, Nor Azam Ramli2, Ahmad Shukri Yahaya3

1 Department of Engineering Science, Faculty of Science and Technology, Universiti

Malaysia Terengganu, 21030 Kuala Terengganu, Terangganu, MALAYSIA

2, 3 Clean Air Research Group, School of Civil Engineering, Engineering Campus,

Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, MALAYSIA.

Email: [email protected]

ABSTRACT. Malaysia has experienced several haze events since the 1980s as a

consequence of the transboundary movement of air pollutants emitted from forest

fires and open burning activities. During the haze periods, airborne particulate

matter (PM10) was found as the major pollutant while the other air quality

parameters remained within the permissible healthy standards. The aim of this study

is to determine the best distribution model that will be used to predict the probability

of exceedences and the return periods for PM10. General probability distributions

(i.e., Beta and Inverse Gaussian) were chosen to analyze the PM10 concentrations

data at two different sites in Malaysia represent industrial area namely Johor Bahru

(Johor) and Nilai (Negeri Sembilan). The best models representing the areas were

chosen based on their performance indicator values. The best distributions provided

the probability of exceedances and the return period between the actual and

predicted concentrations based on the threshold limit given by the Malaysian

Ambient Air Quality Guidelines (24-h average of 150 μg/m3) for PM10

concentrations. Results indicated that Beta distribution represents the data better

than Inverse Gaussian distribution model for both sites. The proposed distributions

were successfully used for estimation of exceedences and predicting the return

periods of the sequence year. The best model found in this study was used to

forecast the upcoming haze weather in Malaysia. This information can be used as

basis for issuing advanced warning to the public, such as in cases when prior PM10

could reach its peak concentration at a given day.

KEYWORDS. Beta distribution, Inverse Gaussian distribution, Exceedences, Return

period


23

C-03

EFFECTS OF MOISTURE ON THE STRENGTH OF CROCKER FORMATION SOIL ALONG KOTA

BELUD – RANAU ROAD, TAMPARULI, SABAH.

Mohamed Ali Yusof Bin Mohd Husin & Baba Musta

Geology Programme, School of Science and Technology,

Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah.

Email : [email protected]

ABSTRACT. In Malaysia, landslide are typically associated with heavy rainfall, it is

believe that an increase in the water content of a soil leads to a reduction of the

stability of natural slopes. The research area is located along Kota Belud – Ranau

Road in Tamparuli, it is underlain prominently by Crocker Formation aged from Late

Eocene to Early Miocene. The objective of the study is to determine the effects of

moisture on the strength of various soils from different lithology. Soil of the area is a

weathering product from the exposed sedimentary rock formation known as

Crocker, the alternating different lithology of this formation from one sampling

station to another reflects the diversity in terms of engineering properties. Based from

the Particle Size Distribution Analysis soils from the study area are classified from clay

to sand materials. Moisture data obtained from the Proctor Compaction Test was

applied using the manipulation of Unconfined Compression Test by treating the

samples with 5% of increment and decrement of moisture from the optimum

moisture content. The analysis yielded the strength of soil ranges from 49.5 kPa to

114.5 kPa for optimum moisture, 12.5 kPa to 50 kPa for 5% increment and 77 kPa to

222 kPa for 5% decrement. The term Shear Strength Difference is introduce in this

research, it is define as the percentage of Sample S2 with clayey material scored

75%, the highest percentage of shear strength difference loss when treated with 5%

increase of moisture; it’s a difference from 99 kPa of the shear strength with optimum

moisture to 25 kPa of the shear strength of 5% increase of moisture. Whilst, sample S6

with sandy material scored 145%, the highest percentage of shear strength

difference gain when treated with 5% decrease of moisture; it’s a difference from

90.5 kPa of the shear strength with optimum moisture to 222 kPa of the shear strength

of 5% increase of moisture. It is observed that engineering properties of soil in the

study area provide variety of results and this mainly controlled by the type of soil. This

research shows that effect of moisture to the properties of the sample has a direct

impact on the shear strength of soil.


24

C-04

THE STABILITY OF TEMBURUNG FORMATION IN BEAUFORT AREA, SABAH

Ismail Abd Rahim

Natural Disasters Research Unit, School of Sciences & Technology,

Universiti Malaysia Sabah, Jalan UMS

88400 Kota Kinabalu, Sabah, Malaysia

Phone: 088 320000 (5734/5999)

Fax: 088 435324

[email protected]

ABSTRACT. The aim of this paper is to determine the stability and to propose

preliminary rock cut slope protection and stabilization measures for Oligocene to

Late Eocene Temburung Formation in Beaufort, Sabah. Six (6) slopes were selected

for this study. Geological mapping, discontinuity survey, kinematic analysis and

prescriptive measure were used in this study. Results of this study conclude that the

modes of failures are wedge, planar, circular and complex. Gunite, soil nail, weep

hole, slope reprofiling, terrace, drainage and retaining structure are proposed

stabilization and protection measures for the slope in the study area.

KEYWORDS. Temburung formation, Beaufort, mitigation measure, slope stability,

mode of failure



25


26

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27

C-06


28

C-07


29

C-08


30

C-09


31

C-10


32

KERTAS

KERJA


33

PRELIMINARY STUDIES OF CONSTRUCTION MATERIALS UNDER TROPICAL CLIMATE EFFECTS

Nauwal Suki1 & Mohd Hisbany Mohd Hashim2

1,2Faculty of Civil Engineering, Universiti Teknologi MARA,

Shah Alam, Selangor, Malaysia

ABSTRACT. Concrete and steel combination has been used in the construction industry for

years and it is undeniable that it has successfully constructed various structures. However,

tropical climate effects such as the sun rays, chemicals from the rain or other particles that

are brought by the wind causes corrosion and thus may affect the structures. This study was

done in order to know the extent of durability of concrete and steel under the harsh tropical

climate effects and the results shall prepare us for the problems that may arise. Through this

study, eight concrete cubes of grade 30 were cast and then cured for 7 and 28 days. The

cubes were then divided and placed in two different areas; one is an area which has a room

temperature surrounding while the other is exposed to the tropical climate. These cubes

were placed there along with steel for a period of three and six months. Once the exposure

time has lapsed, two tests were done to test the mechanical properties of both construction

materials. Concrete had undergone compression test while steel had undergone tensile test.

After the tests were done, it was shown that the materials which were placed in room

temperature surrounding are more durable and stronger as compared to its counterpart

which were placed in the exposed areas.

KEYWORDS. Preliminary studies, Construction materials, Tropical climate.

INTRODUCTION

Concrete and steel are used for construction because these two items need one another.

Concrete has a low tensile strength and needs steel to support it. Steel on the other hand has

a high tensile strength but faces the problem of corrosion if not covered or protected

properly. This is why steel needs concrete to protect it.

We often assume that if a reinforced concrete structure is designed properly, it can stand in

any environment or temperature range without us worrying. We also fail to notice that the

deterioration of concrete may also be caused by other elements, one of which is climate.

Climates are activities that happen within the earth’s atmosphere. The examples are rain,

snow, wind and temperature. Climates depend on the location with different countries

having different climate activities. Based on observations, the deterioration and failure of

buildings occurred due to temperature changes between summer and winter, effects of rain

water and particles carried by wind as well as polluted air (Yaldiz, 2010), heavy loads of snow

on the building and also tougher climate conditions such as hurricane (Kim, 2001) and

chemical reactions that are accelerated by increased temperature and are also influenced

by the humidity (Skalny et al., 2002). Deterioration and failure of structures cost a lot of money

in order to repair the damages and it is a clear reminder on how vulnerable the effects of

climate are. Aware of the signals given by Mother Nature, the climatologists around the

world started finding ways to detect and control changes in extreme weather (Zwiers and

Zhang, 2003). Under tropical climate effects, which is rain and sunny throughout the year, will

cause corrosion to occur. The corrosion, although small in amount, causes small concrete

spillage. Soon, the spillage will grow in size and thus exposing the steel inside the concrete.


34

This situation will then lead to an unexpected modification of the physical properties which

weakens the steel’s tensile strength.

MATERIALS AND METHODS

Concrete cube samples

Eight concrete cubes grade 30 were cast in this study. All concrete cubes with size of 150mm

x 150mm x 150mm were used according to BS8110-4:1997. After the concrete were cast and

left to harden, they were cured in the curing tank for a period of 7 and 28 days. For the

curing process to run smoothly, the curing tank needs to have a temperature between 22oC

to 25oC. (Hamzah et al., 2008). After 28 days, the excess cubes were removed from the

curing tank and placed in two different areas. One area has room temperature settings

while the other is exposed to the tropical climate for the periods of 3 and 6 months. All these

cubes were then tested using a 3000kN compression machine as shown in Figure 1.

Steel samples

The standard codes for reinforcement which were used in this study are BS4449:1998 and

BS4482:1985. Nine steel rods were used in this study. The steel rods were divided into three

different functions. Three rods were used as control samples, another three rods were

exposed for a period of 3 months while the last three rods were exposed for a period of 6

months. All the steel rods have a diameter of 12mm with a tensile strength of 460N/mm2.

These steel rods were cut 750mm in length. They were then tested using the universal Testing

Macine (UTM) which has the capacity of 1000kN as shown in Figure 2. Using the UTM, steel is

gripped on both sides; lower part and upper part. The lower part of the grip is a fixed grip

while the upper part is a moving grip. The Extensometer is attached to the steel to measure

the elongation.

Figure 1. Compression Test Figure 2. Tensile Test


35

RESULTS AND DISCUSSIONS

Compression Test

Concrete is a material which has high compression strength. Concrete strength can be

determined through compression test. Compression test is able to give us a view of the

quality of concrete in its hardened state. Compression test is done to determine the

maximum compressive strength and the maximum load that a concrete could bear. Table 1

shows the tabulated data for compression test for the periods of 7 and 28 days. Based on the

data, the concrete is seen to have properly developed in proportion to the period of days it

takes to cure.

Table 1. Compression Test Results for 7 and 28 Days.

Cube

ID

Weight

(g)

7 Days 28 Days

Compressive

Strength

(N/mm2)

Maximum

Load

(kN)

Compressive

Strength

(N/mm2)

Maximum

Load

(kN)

Cube 1 7923.6 24.48 550.8 - -

Cube 2 8012.2 22.41 504.2 - -

Cube 3 7954.4 - - 31.50 708.8

Cube 4 7796.7 - - 29.18 656.4

After 28 days, the excess cubes were removed from the curing tank and placed in two

different areas. One area has room temperature settings while the other is exposed to the

tropical climate for the periods of 3 and 6 months. Upon reaching the exposed periods,

compression test was done unto the concrete cubes and the data was tabulated and can

be seen in Table 2. The curve for compression test data was plotted in Figure 3. It was found

that the compression strength of the cubes that were exposed did not reduce or deteriorate

from the original grade (grade 30). That being said, the compressive strength did reduce and

the maximum load that they could bear was less when compared to the cubes placed in

room temperature settings.

Table 2. Compression Test Results for 3 and 6 Months

Cube

ID

Condition

Weight

(g)

3 Months 6 Months

Compressive

Strength

(N/mm2)

Maximum

Load

(kN)

Compressive

Strength

(N/mm2)

Maximum

Load

(kN)

Cube 5 Room Temperature 7680 36.79 827.7 - -

Cube 6 Tropical Climate 7760 33.97 764.3 - -

Cube 7 Room Temperature 7640 - - 36.82 828.4

Cube 8 Tropical Climate 7800 - - 35.54 799.7


36

Figure 3. Compressive Strength versus Number of Days Curves

From the physical side of the observation, the tropical climate effects did not provide

extreme effects to the concrete. The concrete cubes which were exposed for 3 months has

the same physical attributes when compared to the cubes placed in room temperature

settings; in short, there were no physical changes. This can be seen in Figure 4(a). Figure 4(b)

shows the concrete cubes that were exposed to tropical climate for 6 months. There were

slight colour changes in certain areas and small stone spillage at the edges of the cubes.

(a) 3 Months Exposed (b) 6 Months Exposed

Figure 4. Concrete Cubes Exposed to Tropical Climate

Tensile Test

Tensile test is done to determine the tensile strength. Tensile strength is the most important

property for steel. Tensile test can also provide the data for elongation at fracture. Table 3

tabulates the average data for maximum load; tensile strength and deformation while Figure

5 shows the tensile strength data versus deformation which has been plotted. It was found

that after being exposed, the load that can be bore was reduced. The tensile strength was

also reduced. Moreover, the elongation of steel at rupture was seen to be longer.

Table 3. Tensile Test Results for Control and Exposed Steel Samples.

Condition Load

(kN)

Tensile Strength

(N/mm2)

Deformation

(mm)

Control 86.23 762.45 25.38

3 Months Exposed 85.60 756.89 25.82

6 Months Exposed 83.72 740.29 29.51


37

Figure 5. Tensile Strength versus Deformation Curves

Figure 6 shows steel failure at rupture. All steel rods faced ductile failure. Figure 6(a) is the

control steel sample, Figure 6(b) is the steel exposed for 3 months and Figure 6(c) is the steel

exposed for 6 months. As time goes by, it was seen that the oxidization process became bad

to worse. It is seen that the steel exposed for 3 months was partially oxidized while the steel

exposed for 6 months was almost completely oxidized.

(a) Control (b) 3 Months Exposed (c) 6 Months Exposed

Figure 6. Steel for Control, 3 and 6 Months Exposed Samples


38

CONCLUSION

Steel is used in construction to support concrete to withstand under tensile and thus avoid

cracking. To ensure that steel remains strong and concrete does not crack, both need to

always be strong and support each other. Due to tropical climate effects, the strength of

steel was reduced. To avoid the unwanted condition to happen, the concrete needs to be

ensured that it can properly protect the steel. Maintenance need also be done often to

ensure concrete spillage due to tropical climate effects does not increase and the concrete

will properly protect the steel within its expected lifetime. We have to take the climate

impact into the design and construction process. Further research needs to be carried out for

different regions so that strategies can be identified and can cope with expected climate

risks. If designed properly; with consideration of climate effects, the combination of these two

materials can produce a structure that can withstand various conditions. However, the results

of current research about the durability of these two materials under tropical climate effects

are scattered in journals and are only mentioned a little in different journals or in text books or

revision books. It is hoped that more insight and information will be found which in the end

reduce the gap of study regarding tropical climate effects to construction materials.

REFERENCES

British Standard Institution, (1997), BS8110-1 Structural Use of Concrete: Code of Practice for

Design and Construction, Milton Keynes:British Standard Institution

British Standard Institution, (1988), BS4449 Specification for Carbon Steel Bars for the

Reinforcement of Concrete, Milton Keynes, British Standard Institution

British Standard Institution, (1985), BS4482 Specification for Cold Reduced Steel Wire for the

Reinforcement of Concrete, Milton Keynes, British Standard Institution

Jan Skalny, Jacques Marchand and Ivan Odler, (2002), Sulfate Attack on Concrete, SPON

Press

Kim, R. L., (2001), Effects of Climate Change on Built Environment, Norwegian Building

Research Institute (NBI).

Siti Hawa Hamzah, Nor Hayati Abdul Hamid and Mat Som Marwi, (2008), Understanding

Reinforced Concrete Through Experiment (2nd Edition), University Publication Centre (UPENA)

Yaldiz, E., (2010), Climate Effects on Monumental Buildings, 4th International Scientific

Conference on Water Observation and Information System for Decision Support,

BALWOIS2010, Ohrid, Republic of Macedonia, 25-29 May 2010.

Zwiers, F. W., and Zhang, X., (2003), Towards Regional Scale Climate Change Detection,

Journal of Climate, Vol. 16, Page 793-797.


39

LESSON LEARNT FROM PAST EARTHQUAKES IN MALAYSIA

N.D Abdul Hadi1, N.H Abdul Hamid2 1PhD Candidate, 2Assoc. Prof., PhD,

Faculty of Civil Engineering,

Universiti Teknologi MARA,

40450 Shah Alam,

Selangor, Malaysia.

[email protected]

ABSTRACT. The purpose of this paper is to find the effect of past earthquakes in Malaysia and

to discuss the lesson learnt from past earthquake either in Malaysia or around Malaysia. .This

includes the damages of structure and infrastructure following the earthquake at

neighboring countries such as Sumatera, Philippines and others. The 2004 Aceh earthquake

and 2009 Sumatra Earthquake are two of the most strong and distant earthquake which has

significant effects to Malaysia. The level of damages on tall buildings in Malaysia following

the earthquakes was found to be slightly damage with minor cracks on the walls and beam

even though at a distance as far as 350km from epicenter. The residents of high rise building

in Selangor and Penang felt tremors after earthquake and it is reported that the high intensity

of the earthquake caused some cracks on the multi-storey building. Cracks in structural

members indicate that this structure which designed according to BS8110 (without seismic

loading) is vulnerable to moderate and severe earthquake. In order to prevent the

formation of cracks, a suitable seismic design code of practice should be adapted. It is

advisable for Malaysia to adapt Eurocode 8 (EC8) in order to avoid further damage of

buildings under high intensity of earthquake in Malaysia.

KEYWORDS. Moderate Earthquakes, Seismic Hazard

INTRODUCTION

Seismicity of an area refers to the frequency, type and size of earthquakes experienced over

a period of time. Malaysia is located on a relatively stable Sundaland block which forms the

southern edge of the Eurasian plate (Azhari, 2012) and it is known to have low seismicity

region. Two main sources have been identified as the contributors to earthquake hazard in

Peninsular Malaysia, namely the Sumatra strike-slip fault and Sumatra subduction zone. It is a

fact that the nearest earthquake fault line in Malaysia which is located in Sumatra comprises

of Sumatra subduction zone and Sumatra fault line with more than 350 km away from Klang

Valley. However, every year, the tectonic plates are moving closer to Malaysia at a rate of

70mm/year. Therefore, precaution steps should be made to prepare the Malaysian from

devastating event and to learn from other earthquakes occurs around the world. The

objective of this paper is to highlight the lessons learnt from previous earthquake in Malaysia

as well as the possible effect that may occur at structures and to provide a viable solution in

preparing for future earthquakes either in or around Malaysia. Figure 1 shows the Sumatran

fault line and subduction of the Indian-Australian Plate and Eurasian Plate. Malaysia has not

experienced high intensity earthquake except for the ones from the neighboring countries.

Up to date, only the 2004 Banda Aceh earthquake had caused the most casualties in

Malaysia due to the tsunami effect especially at northern part of Peninsular Malaysia.


40

Figure 1: Sumatran fault and subduction of the Indian-Australian Plate and Eurasian Plate

(Balendra et al. 2001).

EARTHQUAKES IN MALAYSIA

Most of the earthquakes that occurred in Malaysia in the past 10 years are mainly in Sabah

with its epicenters in Lahad Datu, Kudat and Ranau with a range of 4.5 to 5 magnitudes.

These earthquakes are caused by the fault lines in Sabah such as Mendasan fault line and

Lobou-Lobou fault line. However, there were some phenomena recorded in Peninsular

Malaysia such as sink hole in Ipoh and Batu Gajah, tremors in Bukit Tinggi area in 2008 and

tremor at Jerantut in 2009 (Omar, 2009). In a more recent event, the Malaysia Meteorological

Department(MMD) reported that a mild earthquake of magnitude 3.8 Richter scale struck

Kupang with its epicenter located at 11km south of Baling. The phenomena might triggered

by the large earthquake events in neighboring countries. The local earthquakes in Peninsular

Malaysia are the results from the few inactive fault lines namely, Bukit Tinggi Fault, Kuala

Lumpur Fault, Lebir Fault, Baubak Fault and Mersing fault which is situated across the states as

published by the DMGM in 2008 as shown in Figure 2.

Figure 2: Location of major and minor fault lines in Peninsular Malaysia (DMGM, 2008)


41

However, the tremors that were felt in Peninsular Malaysia usually come from the long distant

earthquake with its epicenter in the neighboring country, namely, Sumatera. The 2002

Northern Sumatra earthquake which causes tremors in west Peninsular Malaysia occurred as

a result of thrust faulting on the boundary between the subducting Australian plate and the

overriding Sunda block of the Eurasian plate (Azlan et al., 2002). Malaysia is also one of the

countries that were affected by tsunami from Banda Acheh, Sumatra. Tremors were felt in

several cities in states of Peninsular Malaysia such as Penang and Selangor. High magnitude

earthquake can cause a great impact to the surrounding location and also to those located

far from its epicenter. The high frequency earthquake waves damped out rapidly in the

propagation while the low frequency or long period waves are more robust to energy

dissipation and as a result they travel long distances (Balendra and Li, 2008). Therefore, large

earthquake magnitude from Indonesia will always cause tremors to Malaysia.

SUMATRAN SUBDUCTION ZONE

The Sumatran subduction zone is formed by subduction of the India-Australian plate beneath

the Eurasian plate at a rate of about 70mm per year (Hamilton, 1979). The nearest location of

this Sumatran fault line is about 350km to Peninsular Malaysia (Adnan and Irsyam, 2002)

which relatively far from the seismic source zone. However tremors due to the Sumatra

earthquakes had been reported several times in local newspaper. In the last few years,

tremors were felt several times in tall buildings which located in Singapore and Kuala Lumpur,

due to the high magnitude earthquake in Sumatra, Indonesia. Based on past earthquake

events such as the 2004 and 2013 Aceh Earthquake and the 2009 and 2011 Northern

Sumatra Earthquake, the range of earthquake magnitude in Indonesia that caused tremors

in Malaysia is within the range of 6.1 to 9.3 scale magnitude. Figure 3 shows the location of

epicenters of the earthquake which located along the Sumatran fault. Even though Malaysia

is situated at more than 300km away from the epicenters, the earthquake can be threat to

the residents who live in high rise buildings in Malaysia especially in West Peninsular.

Figure 3. Location of epicenters of earthquake in Sumatran fault (USGS, 2002)


42

According to the historical records in the last 300 years, four great earthquakes have

occurred in Sumatera sismic zone (Balendra and Li, 2008). Major tectonic feature of Sumatra

seismic area is the Sunda Arc which extends between the Andaman Island in the northwest

and the Banda Arc in the east which results in the subduction of the Indo Australian plate

beneath the Sunda Shelf to a stable southern prolongation of the Eurasian plate. The

frequency and magnitude of this subduction zone seismicity is influenced by the age,

composition, and rate of convergence of the subducted plate. The largest thrust-fault

earthquakes in the Sumatra subduction zone in the last two centuries were that of 1833,

which had a magnitude of 8.8 to 9.2, and that of 1861, which had a magnitude of 8.3 to 8.5

(Adnan and Irsyam 2002). The Sumatran Subduction Zone is also influenced by strike-slip

faulting as a result of the component of plate-motion that is parallel to the trend of the plate

boundary in the interior of the island of Sumatra. Figure 4 shows the Sumatran subduction

zone and Sumatran fault line which located at the offshore and inland, respectively.

Figure 4: The Sumatran Subduction Zone (Adnan and Irsyam, 2002)

SEISMIC HAZARDS IN MALAYSIA

The study of the expected earthquake ground motions at the surface of the earth, and its

likely effects on existing natural conditions and man-made structures is important in

preparation of future earthquake in Malaysia. The most common parameters that are

considered in seismic hazard assessment are recurrence rate and maximum magnitude of

earthquake from future source. Delfebriyadi (2011) studied the seismic hazard analysis to

predist the peak ground acceleration (PGA) at bedrock of Kuala Lumpur. It was found that

at a return period of 475 years, the PGA is 0.08g while Sooria et al (2012) proposed that a

maximum earthquake magnitude in Peninsular Malaysia is 6.5 and the allowable

displacement due to ground motion is 150mm. This falls under moderate earthquake,

therefore, structures in Malaysia should have seismic provisions in order to resist earthquake

excitation in the future.

It is well recognized that ground motions due to earthquakes are affected by the

earthquake source condition, the source-to-site transmission path, and site conditions

(Huang, 2013). Balendra and Li (2008) conducted a research on seismic hazard in Malaysia

through attenuation model. It was found that the major reason that resulted in an obvious

ground motion at a great distance is due to the types of soil. The bedrock motions can be

significantly amplified when the natural period of the soft soil is close to the predominant

natural period of the bedrock motions, and can be further enlarged if the building possesses


43

a natural period which is close to the natural period of the site. Putrajaya and Klang are

sitting on soil that is most susceptible to tremors. Therefore, it explains the shaking felt by the

residents of high rise building. Although Malaysia is situated at low seismic region, it is very

important to not neglect the possible earthquake effects. Figure 5 shows the seismic hazard

map for Indonesia and Malaysia which can be used as the basis of seismic design of building

and infrastructures for the closer location and place.

Figure 5: Seismic Hazard Map in Indonesia and Malaysia (USGS, 2008)

LESSONS LEARNT FROM PAST EARTHQUAKES

Damages, Retrofitting and Code of Practice

Earthquake can cause buildings to collapse, loss of lives and also affect downturn economy

for particular countries. Most of reinforced concrete structures in Malaysia are not able to

resist moderate or major earthquake since they are designed according to BS8110 which has

no seismic provisions at all. Some of the common deficiency includes poor reinforcing

detailing, low concrete strength and inadequate construction quality of members causing

strong beam weak columns phenomena. Therefore, it is of great concern that the strength,

ductility, and energy dissipation capacity of these frame structures may not be adequate to

sustain earthquake-induced loads due to the lack of reinforcement details in this type of

structures (Li and Pan, 2004). One of the most common damage found on reinforced

concrete column subjected to earthquake loading is shear failure. It usually occur as a result

of inadequate transverse reinforcement in the joint and weak-column/strong-beam design

(Ghobarah and Said, 2002). For non-ductile design structures, joint shear failure is very

common when subjected to earthquake excitation. Under seismic loading, it is important for

an RC building to have resistance against brittle failure as it does not have high ductility.

Since demolishing and reconstructing buildings are not a great option due to economic

reasons, retrofitting them at a small fraction of total cost of a new building may offer a

workable solution for ensuring the safety of the people.

Although Peninsular Malaysia has experienced shaking due to mild earthquake, no

significant damage has ever occurred in any multi storey reinforced concrete buildings.

However, in East Malaysia, past earthquakes and ground deformation have resulted in

extensive damage to infrastructures in the area, specifically to schools and teacher’s

quarters (Mohamed, 2012). Buildings of operational damage can be retrofitted suit to


44

damage conditions. Other precaution in preparing Malaysia towards earthquake is

developing an appropriate seismic code of practice such as Eurocode 8 to replace BS8110

in designing multi storey reinforced concrete buildings. Therefore, Malaysia should adapt the

seismic design code of practice in reinforced concrete and steel building, especially for high

rise buildings to avoid experiencing major structural damages during an earthquake.

CONCLUSION

A detail review on seismic hazard study of the regions near Peninsular Malaysia and Sabah

and Sarawak has shown that it is not impossible for large magnitude earthquake will occur in

Malaysia. The findings from historical records states that the earthquakes that influence

Peninsular Malaysia originated from two earthquake faults: Sumatran subduction zone and

Sumatran fault. With the short gap of earthquake events in Sumatra, there is a big possibility

for moderate to high earthquake to occur in Malaysia. Seismic risk studies is important prior to

the construction of vital facilities even though the structures are situated in low-seismicity

regions that are dominated by large-magnitude and distant earthquakes. Although there is

no large earthquake has ever happened in Malaysia, it is very important for authorities and

owners of buildings to have awareness on the possibilities of large earthquake events in

Malaysia in the future.

References

Adnan, A. and Irsyam, D. 2002. The Effect Of The Latest Sumatra Earthquake To Malaysian

Peninsular. Jurnal Kejuruteraan Awam (Journal Of Civil Engineering), 15 (2),

Balendra, T., Lam, N. T. K., Wilson, J. L., and Kong, K. H. 2002. Analysis of long-distance

earthquake

tremors and base shear demand for buildings in Singapore. Engineering Structures,

Vol. 24, No.1, pp 99-108.

Balendra, T. and Li, Z. 2008. Seismic Hazard of Singapore and Malaysia. Electronic Journal

of Structural Engineering Special Issue,

Department of Mineral and Geoscience Malaysia, 2008, The Seismotectonic Map of

Malaysia

(3rd eddition), Mesy.Kumpulan Kerja Geodetik Bil 1/2008, Jupem, Kuala Lumpur.

Ghobarah , A. and Said, A. 2002 Shear-strengthening of beam-column joint. Journal of

Engineering Structures , 24 (1), p.881-888.

Hamilton, W. B., 1979, Tectonics of the Indonesian region, U.S. Geological Survey Professional

Paper 1078, 345 pp.,

Huang, L. 2013. Seismic risk study of a low-seismicity region dominated by large-magnitude

and distant earthquakes. Journal of Asian Earth Sciences, 64 (1), pp. 77-85.

Kanamori, H. and E Brodsky, E. 2004. The physics of earthquakes. Reports on Progress in

Physics, 67 (1) pp. 1429-1496.

Li, B. and Pan, T. 2004. Seismic Performances Of Reinforced Concrete Frames Under Low

Intensity Earthquake Effects. 13th World Conference on Earthquake Engineering,

(3402),

Mohamed, A. 2012. Monitoring Active Faults in Ranau, Sabah Using GPS *. Nineteenth

United Nations Regional Cartographic Conference for Asia and the Pacific.


45

Otani, S. 2013. Lessons Learned From Past Earthquakes.

Delfebriyadi. Seismic Hazard Assessment Of Kuala Lumpur Using Probabilistic Method.

2011. Malaysian Journal of Civil Engineering, 23 (2), pp. 39-53.

Zaini Sooria, S., Sawada, S. and Goto, H. 2012. Proposal for Seismic Resistant Design in

Malaysia: Assessment of Possible Ground Motions in Peninsular Malaysia. Annuals

of Disaster Prevention Research Institute, (55 B), p. 81.

Petersen, M., Hamsen, S., Mueller, C., Haller, K., Dewey, J., Luco, N., Crane, A., and Rukstales,

K., 2008. Documentation for the Southeast Asia Seismic Hazard Maps.

U.S Geological Survey, 2008. Seismic Hazard Map of Western Indonesia


46

THE IMPACT OF TROPICAL CYCLONES IN THE WESTERN PACIFIC OCEAN AND SOUTH CHINA SEA

ON THE RAINFALL IN MALAYSIA

Munirah Binti Ariffin and Subramaniam Moten

Research Section,

Malaysian Meteorological Department,

Ministry of Science, Technology and Innovation (MOSTI),

Jalan Sultan, 46667, Petaling Jaya,

Selangor, MALAYSIA.

ABSTRACT. Tropical cyclones (TCs) are intense synoptic systems that significantly modifies the

basic atmospheric state through the entire troposphere. This has a strong influence on the

regional rainfall pattern, even to countries that are not directly on the path of these

cyclones. The Malaysian region is in close proximity to one of the most active cyclogenesis

region in the world, that is the West North Pacific (WNP) and the South China Sea (SCS)

region. This region has the highest number of tropical cyclones globally with an average of

27 cyclones per year, with nearly half of them reaching typhoon intensity. September has the

highest number of tropical cyclones with an average of 5.4 cyclones occurring in a year,

while February records the lowest number of tropical cyclones. In this study 57 years of

tropical cyclone data from the Regional Specialized Meteorological Centre (RSMC) - Tokyo

and rainfall data for the same period from selected principal meteorological stations in

Malaysia is used to study the impact of tropical cyclones on the rainfall in three Malaysian

regions; Sabah, Sarawak and northwestern Peninsular Malaysia. The probability of rainfall at

different stages of the cyclone and their location in the WNP and SCS reveals that the rainfall

has a higher probability of occurrence when the cyclone is in the open sea, whereas over

northwest Peninsular Malaysia it is during landfall or close to the Indochina coast the

probability is higher. When the TCs are in the SCS, Sarawak has a higher chance of getting

rain than when the TCs are in WNP. Though the chance of receiving rain when TCs are

located in WNP or SCS is more than 70 percent, but there is less than 40 percent chance of

getting heavy rain (>10mm). For Sarawak and northwestern Peninsular Malaysia when the

TCs are located in the SCS the chance of rain increases as the TC category increases from

depression to typhoon stage. For Sabah when the TCs are located in WNP, the probability of

rain is higher when the TCs are at the tropical storm stage as compared to other stages.

KEYWORDS. Tropical cyclones, cyclone’s intensity, rainfall distribution and rainfall probability.

Introduction

Frequency of occurrences of tropical storms varies widely within the globe. The Western

North Pacific Ocean (WNP) and South China Sea (SCS) is the most active basin for tropical

storms genesis (Figure 1), while there is almost no activity in the Atlantic Ocean south of the

equator. Typhoons are three times as likely to develop in the WNP Ocean compared to any

other area in the world (Ramage,1959). Climatologically, tropical storms frequency in the

WNP is higher than any other basin, with an annual mean of 26 based on 22-year statistics

from 1968 to 1989 (Neuman, 1993). The main contributing factors are; i) the warmer sea

surface temperature (SST) over the Western Pacific and SCS, which is typically greater than

28°C for most part of the year and is the key driver of tropical storm formation (Trentberth,

2007). ii) The WP is a large basin; so any formation of tropical storm (TS) can have enough

time to intensify from a tropical depression to typhoon.


47

Figure 1: Map of all global tropical storm tracks from 1945 to 2006 (Source: Wikipedia)

The presence of tropical storms in WNP or SCS, will alter the regional tropospheric synoptic

circulation patterns, impacting the weather over the Asian monsoon region in the short term,

depending on the stage of the storm intensity and location. Kumar and Krishnan (2005)

analyzed 56 years of storm track data and daily global wind data and they found that large

scale circulation anomalies associated with the inter-annual variability of the Indian monsoon

play an important role in influencing the tropical cyclone activity. Their study revealed that

during weak monsoon years the cyclogenesis over west Pacific is about 33 percent higher

compared to strong monsoon years. Rajeevan (1993) found that the Indian summer

monsoon rainfall and the number of typhoon days in the NW Pacific are negatively

correlated. The planetary circulation pattern will also be perturbed depending on the

duration and intensity of the storm, which will influence the seasonal weather on a much

larger scale. Conversely, large-scale circulation anomalies may also significantly affect the

formation and tracks of cyclonic disturbances in the west Pacific. One of the most studied

relationships is between TC activity and the El Nino Southern Oscillation (ENSO) phenomenon.

Studies by Chan (1985, 2000) shows that the year following a large negative Southern

Oscillation Index (SOI) there is an overall reduction in TC frequency over the WNP and vice

versa. Kimberlain (1999) found that the life cycle of tropical storms and typhoons in the WNP

is nearly 1.5 times longer during El Nino years as compared to La Nina Years.

Latitudinal strategic location of our region confined between equator and 8°N keeps

Malaysia from being vulnerable to the direct impact of tropical storms except on three

occasions, namely; in December 1996 (TS Greg), January 1999 (TS Hilda) and December 2001

(TS Vamei), where TS formed off the Malaysian coast in the South China Sea. TS Greg made

landfall over Sabah and Vamei was the most unusual and unique tropical storm to develop

so close to the equator (1.5°N) and moved across southern Peninsular Malaysia. Tropical

storms rarely develop within 5° of the equator since within this region coriolis force is

negligible, a force that is required for the initiation of cyclonic flow. TS Vamei is thought to

have being maintained by cyclostrophic balance. Although Malaysia is spared from the

direct hit by tropical storms, except for the two occasions in known historical records, but

presence of TCs in WN Pacific and South China Sea influences the synoptic circulation over

the region which has an indirect impact on the weather over Malaysia. The objective of this

study is to examine the impact, the storms intensity and position has on the rainfall over

different parts of Malaysia, in particular the states of Sabah and Sarawak in East Malaysia

and Northwest Peninsular Malaysia.


48

Data

Data used for this study include tropical storms best track data (1951 - 2007) obtained from

Regional Specialized Meteorological Centre (RSMC) - Tokyo. RSMC - Tokyo is a WMO

designated center that monitors, issues advisories, warnings and forecasts about tropical

storms in its designated area of responsibility that extend eastward of 100°E to the dateline

and from equator to 60°N. The RSMC best-tracks data contain six-hourly tropical storm

information including the storms position (latitude and longitude), storm's central pressure

(SCP), 10-minute maximum sustained wind speed (MSWS), and the different stages of the

storms intensity. For the earlier years from 1951 to 1976 neither the MSWS nor the storm

intensity are included. Only tropical depressions (stage 2) and extra-tropical storms (stage 9)

are reported.

Daily rainfall data from fourteen main meteorological stations in Malaysia for the same

period are used in this study. The locations of these stations, five in Sabah, four in Sarawak

and five in Northwestern Peninsular Malaysia (NPM) are shown in Figure 2.

Figure 2: Locations of rainfall stations used in this study

Estimation of TC Stage from Storm’s Central Pressure (SCP)

To determine the different stages of the tropical storm for the period before 1977 the MSWS

needs to be estimated from the central pressure. Regression analysis performed on the data

from 1977 to 2007 depicted a second order polynomial relationship between the MSWP and

SCP (Figure 3) with an R2 of 0.93. An examination of the scatter plot of MSWS against SCP

shows a large spread in the data which by visual analysis would not indicate a good

relationship. MSWS are reported in increments of 5 knots and the frequency distribution of the

data for a particular MSWS and a particular SCP which in this case we have chosen 65 Kts

and 970 hPa respectively (Figures 4a and 4b) shows that a very large percentage of the

data actually lies on the line of best fit, thus giving a very high correlation.


49

(a) (b)

Figure 3: Relationship between MSWP and SCP based on 31 years of data from 1977 to 2007

Figure 4: Frequency distribution of 65 knots of MSWS (a) and 970-hPa of SCP (b)

Using this relationship, the MSWP for the period 1951 to 1976 is computed and hence the

different stages of the tropical storm intensity are determined using the WMO criteria of

tropical storm intensity classification as given in Table 1.

Table 1: MSWS and tropical storm Intensity

MSWS SCP Storm Stage

Less than 35 knots Greater than 999 hPa Tropical Depression (TD)

Between 35 knots and 45 knots Between 985 hPa and 999 hPa Tropical Storm (TS)

Between 46 knots and 64 knots Between 970 hPa and 985 hPa Severe Tropical Storm (STS)

Greater than 65 knots Less than 970 hPa Typhoon (TY)


50

Nu

mb

er o

f TC

(p

er y

ear)

TC Climatology in the Western North Pacific Ocean and South China Sea

In the WNP and SCS, on the average about 27 TC forms in a year, and about half of them

reach typhoon intensity. The average number of TC per year for each of the calendar

months in the WNP and SCS is shown in Figure 5. TCs are most active between the months of

July and October, where on average 18 TC occurs during this four months accounting for

about two thirds of all TC in a year. September records the highest number of TC with an

average of 5.4 TCs.

Month

Figure 5: Average number of TCs in WNP and SCS based on 57 years of data (1951 - 2007).

The full bar (red and blue) indicates TC of intensity TS or higher and the blue portion indicates

TC of typhoon intensity. The number shows percentage of TCs that attained typhoon

intensity.

TCs are least active between January and April, where on the average about 17 TCs occurs

in 10 years. February is the month with the lowest TCs recorded, where only 2 TCs are

expected in 10 years. During northern spring and fall seasons, that is April-May and

September to November, more than half of the tropical storms will reach typhoon stage, with

October being the month having the most number (61%) of tropical storms reaching typhoon

intensity.

The formation, intensification and movement of TC in the WNP and SCS are very much

influenced by the large-scale circulation pattern established by the monsoon (Elsberry, 2004)

and the north-south progression of the monsoon trough. The TC climatology by month

showing the position and the different stages of TC from 1951 to 2007 is shown in Figure 6.


51


52

Figure 6: Monthly variation (January to December) of tropical cyclone track. Data from 1951

to 2007.

It is evident that during the late boreal winter months; January to March, when the monsoon

or near-equatorial trough is generally located south of the equator, few cyclones develop in

the WNP. However, occasionally when there exists a double near-equatorial trough,

cyclogenesis takes place in the WNP between about 5°N and 15°N and the storms generally

track westwards and very few intensify to become typhoons.

In the inter-monsoon season, April to May, more cyclogenesis can be seen over South China

Sea but seldom making landfall over Indochina. With the onset of the northern hemisphere

summer in June, the monsoon trough extends towards the latitude of maximum sea surface

temperature. TC activity over SCS also increases and by this time, many of them start to

make landfall over Indochina. As the summer monsoon advances poleward over East Asia

through August, the eastern anchor of the monsoon trough over Western North Pacific is also

displaced poleward. Formation of the typhoons are more concentrated over the WNP

compared to SCS, and many of these cyclones recurve and make landfall over Japan or

dissipate over the cold waters in the higher latitudes. Southward retreat of the summer

monsoon over East Asia during September to October is also accompanied by the

equatorward displacement of the WNP monsoon trough.


53

During November to December the monsoon trough extends from the western Pacific,

between 5°N and 10°N, to southern South China Sea, between equator and 8°N. In

consonance with the equatorward displacement of the trough, the TC activity too gets

shifted equatorward and closer to the Malaysian region. During this period some of the

storms moves westwards from the South China Sea to the Bay of Bengal.

Method of Analysis

The 57 years of data from 1951 to 2007, classified into four stages according to their intensity

namely; Tropical Depression (TD), Tropical Storm (TS), Severe Tropical Storm (STS) and Typhoon

(TY) respectively are grouped into boxes of 2.5° X 2.5° for the region bounded by 5°N and

30°N and 100°E and 140°E (Figure 7).

Figure 7: Region of analysis

Initial analysis to determine the impact on Sabah’s rainfall according to the SCP not too far

from Sabah showed poor correlation (Figure 8). This analysis shows that during the initial

stages of the storm development the rainfall amount can vary significantly, but as the storm

strengthens the rainfall decreases when storms are located in this particular area of the WNP.

Figure 8: Relationship between Sabah rainfall and SCP for storms

located west of the Philippines (Region B in Figure 7)


54

In order to provide a more meaningful interpretation of the impact of TS based on their

intensity as well as their location in the WP or SCS, the probability of occurrences of rainfall for

different parts of the country, namely; Sabah, Sarawak and Northwest Peninsular Malaysia

(NPM) are computed for different amounts (> 0.0 mm, > 5.0 mm and > 10.0 mm). Probability

of rainfall is computed for each box when the total number of TCs at the referenced stage

exceeds seven. In addition, when the TCs are located in Region C and Region D, the

probabilities of occurrence of rainfall for different threshold amounts from 0.0 mm to 35.0 mm

at intervals of 5.0 mm are computed.

The Impact of TCs at Different Location on the Rainfall in Malaysia

For the case when the tropical storm has attained the stage of TS or higher and its impact on

the rainfall for Sabah, Sarawak and Northwestern Peninsular Malaysia (NPM) are shown in

Figures 9a, 9b, and 9c respectively.

Figure 9a and 9b: Percent chance of Sabah (left) and Sarawak (right) getting rain when

TS/STS/TY is located in their respective boxes.

It is evident that when the storms are over

the open sea, the chances of Sabah

getting rain is more than 80 percent which

decreases to between 60 and 80 percent

when the storms make landfall. For

Sarawak there is more than 80 percent

chance of rain when the storm is over

central SCS and southern Philippines. When

the storms make landfall over the China

Coast, the percentage chance of rainfall

reduces to about 50 percent. The

Northwestern Peninsular Malaysia has more

than 80 percent chance of rain when the

storms are off the Vietnam coast or during

landfall over Indochina. When the storm is

over the Gulf of Thailand there is a 70

percent chance of rain, but when it is

further to the east, over central SCS there is

only a 50 percent chance of rain in

Northwestern Peninsular Malaysia.

Figure 9c: Percent chance of NPM getting rain when

TS/STS/TY is located in their respective boxes

(a) (b)

(c)


55

Figure 10: Percent chance of Sabah getting rain when TD (left) and TY (right) is located in their

respective boxes.

Analyses are carried out for different stages of TS, different rainfall amounts, and at different

positions of TCs. When a TD is located over SCS or WP there is more than 80 percent chance

Sabah will get rain, which decreases to about 70 percent when TD is over the land, that is

when the storm has made landfall and weakened to a TD. When a storm close to Sabah

intensifies, the chances of heavy rain increases (Figure 10).

Figure 11: Percent chance of Sarawak getting rain when TD (left) and TY (right) is located in

their respective boxes.

When TD are located south of 15°N there is more than 70 percent chance of Sarawak getting

rain, which decreases when TD is located north of 15°N. When a storm north of Borneo

intensifies the chances of heavy rain over Sarawak also increases, but the chances are

higher over Sabah (Figure 11).


56

Figure 12: Percent chance of Northwestern Peninsular Malaysia getting rain when TD (left) and TY

(right) is located in their respective boxes.

Figure 13: Percent chance of Northwestern Peninsular Malaysia getting rain when STS (left) and TY

(right) is located in their respective boxes.

When a storm in the SCS intensifies from TD to TS, the probability of heavy rain over NPM decreases

(Figure 12). There is more than 80 percent chance of rain when TD is located or moving inland over

Indochina, but if it is south of Cambodia the chances are 50 to 60 percent. When the TS is over the

WP the chances of rain over NPM increases when TS intensifies to STS (greater than 60 percent), but

decreases when STS intensifies to a TY (less than 55 percent, Figure 13).

Probability of Rainfall at Various Threshold Amounts for Different TC Intensities

The impact of TCs when it is located in the SCS or WNP is examined by way of looking at the probability of occurrences of rainfall exceeding certain threshold amounts, which in this case we have taken from 0.0 mm to 35.0 mm at intervals of 5.0 mm. The probability of rain at different thresholds for the three regions when the TCs are located in the SCS (Region C) and WNP (Region D) are shown in Figures 14 and 15 respectively.


57

Figure 14: Probability of rain over Sabah (left), Sarawak (middle) and Northwestern Peninsular (right) for

eight threshold amounts of rainfall for different storm intensities when TCs are located over the SCS

(Region C in Figure 7).

Figure 15: Probability of rain over Sabah (left), Sarawak (middle) and Northwestern Peninsular (right) for

eight threshold amounts of rainfall for different storm intensities when TCs are located over the WNP

(Region D in Figure 7).

a) Impact on Sabah

When the storm is in the SCS and is at the depression stage, there is an 80 percent chance of

Sabah receiving rainfall which increases to over 90 percent when the TCs are at the TS or

Typhoon stage. For greater thresholds of rainfall at increments of 5mm, the probability of rain

drops exponentially and for heavy rain (> 10mm) the probability of rain decreases to about

30 percent. At all thresholds the chance of rain when the TC is at the severe tropical storm

stage is slightly higher than when the TC is at other stages. The same is true when the TCs are

in the WNP where there is an 80 to 90 percent chance of rain, and drops exponentially for

higher thresholds. For all thresholds up to 25 mm, when the TCs are at the tropical storm stage

the probability is higher compared to other categories by about 10 to 15 percent.

b) Impact on Sarawak

For Sarawak the probability of rain ranges from 70 to 90 percent when the TCs move from

the depression stage to the typhoon stage. For higher thresholds of rainfall the probability of

rain decreases exponentially. For rainfall thresholds up to 30mm the probability of rain

increases when the TCs intensified from depression to typhoon stage. A similar pattern is

observed when the tropical cyclone are located in the WNP, however unlike when the TCs

are located in the SCS, here the different stages of the TC has no significant influence on the

probability of rainfall occurrences.


58

c) Impact on Northwestern Peninsular Malaysia (NPM)

The percentage chance of rain for NPM follows closely to that of Sarawak when the TCs are

in the SCS. For rainfall thresholds of up to 10mm the probability increases with TC intensity. The

difference is about 20 percent going from depression to typhoon category. When the TCs

are in the WNP, the percentage chance of rain is about 70 percent and decreases

exponentially for higher thresholds of rainfall. For all categories of TC the percentage chance

of rain is nearly the same, unlike when the TCs are in the SCS. Also, when the TCs are in the

SCs the probability of rain is higher than when the TCs are in WNP.

Conclusion

The WNP and SCS region is one of the most active regions for tropical cyclone genesis, with

an average of about 27 cyclones in a year occurring over these region, with nearly half of

them reaching typhoon intensity. The boreal summer months and early autumn are the most

active period, with September recording the highest number of TCs at an average of 5.4 TCs

of which more than half will intensify to typhoon stage. The boreal winter months are the least

active period for TCs, with February recording on average two tropical cyclone in ten years.

The presence of these tropical cyclones in the WNP and SCS region has a profound impact

on the rainfall over Malaysia. The impact studied here in terms of probability of rainfall

occurring over three regions in Malaysia, i.e., Sabah, Sarawak and Northwestern Peninsular

Malaysia shows that when the cyclones are over the open sea there is a higher chance of

Sabah getting rain than when the storm makes landfall. For Sarawak when the cyclones are

over the central SCS the chances of rain are high and when the storms make landfall the

chances of rainfall reduces to about 50 percent. In the case of Northwestern Peninsular

Malaysia, when the storms are off the Vietnam coast or making landfall, the chance of rain is

high. There is also some difference in the percent chance of rainfall for all these three regions

when the tropical cyclones are at the different stages of development. Generally it is noted

that all three regions has a high chance, more than 80 percent for Sabah and Sarawak and

more than 70 percent for Northwestern Peninsular Malaysia, of getting rain. For higher

intensities of rainfall the probability of rainfall decreases exponentially, and for heavy rainfall

(> 10.0 mm) the percent chance is about 30 percent on the average.

Acknowledgements

We would like to thank the staff of Research Section for their technical support. We are

particularly indebted to Mr. Tan Kah Poh from the Climate Division for his invaluable

assistance in preparing the rainfall probability maps.

References

Chan, J. C. L., 1985. Tropical cyclone activity in the northwest Pacific in relation to the El

Niño/Southern Oscillation phenomenon. Mon. Wea. Rev., 113, 599–606.

——, 2000: Tropical cyclone activity over the western North Pacific associated with El Niño

and La Niña events. J. Climate, 13, 2960–2972.

Elsberry, R. L. 2004. Monsoon Related Tropical Cyclones in East-Asia. Chapter 13. East Asian

Monsoon (C. -P. Chang, Ed.) World Scientific Press, Singapore, 463-497.


59

Kimberlain, T. B. 1999. The effects of ENSO on North Pacific and North Atlantic tropical

cyclone activity. Proceedings of the 2nd Conference on Hurricanes and Tropical

Meteorology, pp. 250-253. Boston: American Meteorological Society.

Kumar, V., and R. Krishnan. 2005. On the association between the Indian summer monsoon

and the tropical cyclone activity over northwest Pacific. Current Science Association,

Bangalore. Vol. 88, No. 4, pp. 602-612.

Neuman, C. J. 1993: Global overview: Global guide to tropical cyclone forecasting. pp. 1.1-

1.56. Geneva. World Meteorological Organization.

Rajeevan, M., Inter-relationship between NW Pacific typhoon activity and Indian summer

monsoon on inter-annual and intra-seasonal time-scales. Mausam, 1993, 44, 109-111.

Ramage, C. S. 1959. Hurricane Development. Journal of Meteorology, vol. 16, pp. 227-237.

Trenberth, K. E. July 2007. Warmer oceans, stronger hurricanes. Scientific American Inc,.


60

SEISMIC PERFORMANCE OF 3-STOREY TUNNEL FORM SYSTEM BUILDING WITH DOUBLE UNITS

SUBJECTED TO LATERAL CYCLIC LOADING

A. A SHAMILAH, N. H ABDUL HAMID & S. MD SALLEH

Faculty of Civil Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia.

Corresponding author : [email protected]

ABSTRACT. A one-third scale of double unit 3-storey reinforced concrete tunnel form building

(TFB) is investigated. A set of 3-storey reinforced building together with foundation beam are

designed, constructed and tested under quasi-static reversible in-plane lateral cyclic

loading. This building is tested from ±0.01% drift until ±1.0% drift with an increment of 0.25%

drift. The shear wall of tunnel form system started to crack at -0.25% (pulling) drift on wall-slab

(wall 1) connection of the first floor. More cracks occurred as the increment of drift on wall

surface and the connection. The diagonal crack found to form at +1.25% drift on the first and

second floor outer wall 3. The diagonal crack also occurred on the second floor of the outer

wall 1. The maximum in-plane lateral loading recorded for this specimen was 71.84KN at

+1.0% drift. The ductility of TFB obtained from this experiment result is μ = 4.8 which is still in the

range 3 to 6. This showed that TFB performed well under long distant earthquake for minor to

moderate.

KEYWORDS. Tunnel form building system, lateral strength, ductility, stiffness, equivalent viscous

INTRODUCTION

Earthquake is considered as the major causes of fatalities and destroy the properties when its

strike certain area. The major damage caused by past decades earthquakes in Japan,

Taiwan, Iran, China and Italy gives a greater impact on high rise building in urban areas.

These phenomena have spurred many researchers to investigate the performance of high

rise building under seismic motion. (Ionut and Gabriela, 2010). Most of the countries which

are experiencing high intensity of the earthquake had been practicing seismic code since in

1988. Researchers are still investigating the new technology till nowadays in order to increase

the resilience of building structure under earthquake event.

In Malaysia, most of the buildings were designed according to BS8110 which has no provision

for seismic loading. This is because Malaysia is located far away from the most active fault

line in the world. The occurrence of Sumatra Earthquake on 26 December 2004 with a 9.2

scale Richter which triggered a devastating tsunami give a major impact to the west of

Malaysia. Frequent earthquakes have a significant impact on the medium and high rise

building in Malaysia.

Malaysia is still considered as a low seismic region based on earthquakes history. However this

condition cannot be neglected because Sabah had experienced partial damages of

reinforced concrete building within seismic magnitude 4.3 Scales Richter. These levels of

damages indicate that the overall performance of a structure which has been designed

using BS8110 could not sustain under low magnitude of seismic loading. If any unpredicted

earthquake happened within 300km from the epicenter to Malaysia, a major collapse of a

building may occur. This has happened because these buildings were not designed

according to current seismic code of practice. Therefore, it is important to study and identify

the seismic behaviour under Malaysian building design specification.

Malaysia has experienced long-distant earthquake which has caused substantial damage to

the several buildings in this country. Due to this reason, the structure performances under

long-distant earthquakes started to get the more concern and attention from the researcher.

(Taksiah et al., 2007). Moreover, frequent earthquakes which occurred in Sumatra have


61

significant impact on the medium and high-storey reinforced concrete building in Malaysia.

Currently in Malaysia, the IBS method has become the selection for construction industry

especially for high rise building in urban areas. Most of apartment, condominium, offices and

the hotel used tunnel form building system as their construction method.

Tunnel shear wall in the building should have enough strength and capacity to carry the

design loads which come from vertical (gravity load) and horizontal load (wind, landslide

and earthquake loading). It is important for designer and engineer to use the appropriate

strength of concrete and percentage of reinforcement bars in designing and constructing

tunnel shear walls (Garcia and Sozen, 2004). Besides that, RC shear walls should have

enough ductility to avoid brittle failure in order to withstand the greater lateral loading

(Satpute and Kulkarni, 2013). Since tunnel form building system is populated by a high

density of residential, thus the effect of earthquakes on this typical of the building will give a

greater impact. Therefore, the study of tunnel form building performance under earthquake

excitations should be highlighted.

Seismic performances of tunnel form buildings have been observed during earthquakes (Mw

7.4 at Kocaeli and Mw 7.2 at Duzce) in Turkey in 1999. These earthquakes struck the most

populated areas and caused substantial structure damage, casualties and economic loss

(Balkaya and Kalkan 2004). There is a very limited study regarding performance of tunnel

form building under a long-distant earthquake in Malaysia. Thus, this study will fulfill the need

to determine the behavior of tunnel form building system under seismic excitation.

The main objective of this study is to investigate the performance of tunnel form building

system under in plane lateral cyclic loading through experimental work. The seismic

performance of the specimen was evaluated by studying its behavior in relation to strength

reduction, ductility, stiffness and equivalent viscous damping (EVD). Moreover, the damage

patterns obtained during the experimental work also will be discussed in this paper.

METHODOLOGY

In this study, a double unit 3-storey of tunnel form building system have been designed,

constructed and tested under in-plane lateral cyclic loading. The testing is conducted using

lateral cyclic loading machine. The specimen is scaled down to the one third (1/3) from the

actual size due to the limited of working space. The size and dimension of tunnel form

building as shown in Table 1.

Table 1. Dimension and Size for Specimen

Items Description Actual Size Prototype Specimen

1. Foundation* Width = 5850 mm

Length = 4000 mm

Thickness = 500 mm

Width = 2250 mm

Length = 1750 mm

Thickness = 400 mm

2. Shear Wall Height = 2800 mm

Length = 3600 mm

Thickness = 150 mm

Height = 930 mm

Length = 1200 mm

Thickness = 50 mm

3. Slab Width = 2700 mm

Length = 3600 mm

Thickness = 150 mm

Width = 900 mm

Length = 1200 mm

Thickness = 50 mm

* Foundation was not constructed for one third (1/3) scale because to provide a sufficient

size for locating the wall and provide a base of structure for testing on lateral cyclic loading.


62

There were three important stages that involved in this study; design and analysis of 3-storey

tunnel form building system with double units according to British Standard (BS8110),

construction of the specimen and setup instrumentation for testing. The material properties

used in the design and construction as tabulated in Table 2.

Table 2 . Material Properties for Design and Construction for Specimen

Items Material Description Properties

1. Concrete Strength

(a) Foundation

(b) Shear Wall and Slab

40 N/mm2

35 N/mm2

2. Steel Reinforcement Strength

(a) Foundation and Deep Beam


460 N/mm2

250 N/mm2

3. Aggregate Size

(a) Foundation and Deep Beam


20 mm

10 mm

The detail of drawing for the prototype specimen is provided to be a guideline for the

construction as shown in Figure 1.

Figure 1. The scale down prototype specimen.

As the design included the criteria loading as mention earlier, the detailing of reinforcement

is demonstrated in Figure 2. For the construction of slab panel, the reinforcement of mild steel

with size 6mm has been used for both directions of span. The spacing is provided between

bars will be 100mm. The detail of reinforcement has been applied to the whole floors except

for the top floor. The concrete strength of 35 MPa has been adopted for the slab structure.

The size aggregate limited to a size below than 10mm as to allow the space for mixing

concrete overflow to the slab panel area.

The wall panel has been constructed with size 1200 mm (width) x 930 mm (height) x 50 mm

(thickness). The wall is the main component of the structure to cater any loading from the

horizontal and vertical. For this construction of prototype building, the reinforcement of the

wall used is 8 mm diameter of mild steel and 80mm spacing within bars. The transverse bar is

located in a horizontal direction with similar size of bars 8 mm and 200 mm spacing between

bars. Figure 3 illustrates the arrangement of wall reinforcement that have been used in the

construction of the specimen.


63

The primary data that should be provided for testing is the control displacement together

with the increment of drift. The drift is started from 0.01% with increment of 0.25% drift. In this

study, six sets of drift were applied to the top of 3-storey tunnel form building as shown in

Table 3. The graph of control displacement versus number of cycles is shown in Figure 4.

Table 3 . Displacement control for in-plane cyclic loading

Figure 4. Quasi static cyclic loading regime

Figure 5 shows the locations of linear variable differential transducer (LVDT) on the top of the

surface and side of the wall panel. In this study, six LVDTs were used to measure deflection,

rotation and average curvature of the wall when in-plane lateral loading was applied on top

of the wall. The in-plane lateral displacement of the specimen was monitored by LVDT

located on each floor of the specimen.

No. of Cycles Drift (%) Displacement (mm)

2 0.01 ± 0.31

4 0.1 ± 3.08

6 0.25 ± 7.69

8 0.5 ± 15.38

10 0.75 ± 23.06

12 1 ± 30.75

-1.5

-1

-0.5

0

0.5

1

1.5

0 2 4 6 8 10 12 14

Dri

ft(%

)

No. of Cycles

Figure 2. Detail drawing for slab

reinforcement

Figure 3. Detail drawing for wall

reinforcement


64

Figure 5. Experimental set-up and location of LVDTs installed to the specimen.

EXPERIMENTAL RESULT

Visual Observation

From a visual observation during testing, the cracking was starting to occur at ±0.25% of drift.

The first crack was occurred on wall-slab of wall 1 with recorded loading is 25kN. The crack

was occurred in horizontal line which is the tension crack is occurring. The second crack was

occurred on the second floor of the outer wall 3. The third crack occurred on the first floor

inner wall at 0.5% (pulling). The similar crack has happened at every surface of the wall. The

major crack was happening at first floor level, the configuration and explanation were

focused on major crack at first floor level. The second floor was occurred similar as in first floor

level. The top floor was not suffering any cracks as it is free and unrestrained.

The hairline cracks occurred along the first floor of wall at 0.5% (pushing) drift. At the

right edge of the first floor wall, most of the cracks continuously occurred at ±0.75%, ±1.0% ,

and ±1.25% drift. Meanwhile, at the left edge of the same wall, the crack occurred at ±0.75%

drift as shown in Figure 6(a). Finally at the 1.25% (pushing) drift, diagonal crack started to form

on the middle of the second floor of the outer wall 1.

The crack pattern of wall 1 (outer) differs with wall 3 (outer). The crack started to occur at

0.75% (pulling) drift on the first floor outer wall 3. The crack started at the edge of both side

wall and connect at the middle of the wall and form the diagonal crack as shown in Figure..

On the second floor of the outer wall 3, the crack occurred at –0.75% drift, +1.0% drift and

+1.25% drift. The crack pattern similar with first floor (occurred at the edge of wall and across

to each other on the middle of wall). The diagonal crack occurred at +1.25% drift almost the

height of the second floor wall 3 as shown in Figure 6(b).

For the first floor 2, left hand side wall suffered much more cracks compared with the right

one. The crack started to occur at 0.5% (pushing) drift until 1.25% (pushing) drift. About 2

diagonals crack formed on the middle of wall located in the upper part and lower part

respectively on wall 2 (first floor). Both of the diagonal cracks found to be occured at the

1.25% (pushing) drift. At the middle wall, crack obtained from +0.5% drift seems to be

connected with crack obtained from ±0.75% drift along the wall as shown in Figure 6(c).

For the first floor wall 2 (right hand side), the crack started to occur at ±1.0% drift, +0.75% drift

and +1.25% drift. At the left edge of this wall, all of the cracks were obtained from +1.0% drift.

However, on the right edge of wall, the crack seems to be occurred at +0.75% drift and -0.1%

drift. Finally, a crack that occurred from +1.25% drift come across the +0.75% drift crack and

induce a diagonal crack at the middle of this wall as shown in Figure 6(d).

LVDT

1

LVDT 2

LVDT 3

LVDT 4

LVDT 5 LVDT 6

Hydraulic

Jack


65

For the second floor wall 2 (left hand side), the cracks occurred at the right edge of wall at

1.0% (pushing) drift and 1.25% (pushing) drift. Meanwhile at the left edge of the same wall,

only 2 cracks were found to be occurred at ±0.75% drift. There is no crack at the middle of

this wall as shown in Figure 6(e). For wall 2, the second floor (right) suffered much more crack

compared with the first floor wall. The cracks occurred at ±0.75% drift, ±1.0% drift and ±1.25%

drift. The crack pattern of this wall is same with outer wall 1 and 3. The crack started to occur

on the edge of the wall. The crack propagated to the middle of the wall and formed the

diagonal crack at 1.25% (pushing) drift as shown in figure 6(f).

(a)

(b)

( c )

(d)

(e)

(f)

Figure 6. Crack pattern on (a) wall 1 (outer), (b) wall 3 (outer), (c) first floor of wall 2 (left), (d)

first floor of wall 2 (right), (d) second floor of wall 2 (left) and (e) second floor of wall 2 (right)


66

Theoretically, the lateral force which applied to the center of the frame which is directed to

the center of wall 2 will result the maximum stress on wall 2 as compared with wall 1 and wall

3. The distribution of the load is uniformly to each wall by attaching the steel plate between

structure and hydraulic jack. Similarly with earthquake loading which was occurring in

uniform loading but not in concentrated load. For this case, the wall will take similar loading

and the performances of wall having maximum stress at free edge (wall 1 and wall 3)

compare than fully framing support (wall 2). It is observed that much more cracking

appeared on wall 1 and wall 3 surfaces as compared with wall 2 during testing.

Lateral Strength

During the experimental testing, tunnel form building system was imposed with the six sets of

drift. Each drift comprised two cycles to represent the first and second strike of the

earthquake event. This is because in earthquake event, normally there is an aftershock of an

earthquake. Full successive cycle consists of pushing and pulling phase. Pushing cycle was

represented in positive sign and pulling cycle represented in negative sign. In this study, the

displacement has been controlled in order to get the maximum lateral strength of the

specimen.

The lateral strength of the specimen was determined by plotting the hysteresis loop graph.

Figure 7 shows the load and the displacement pattern under push and pull direction. From

the plotted graph load versus displacement below, the maximum load found to be 71.84kN

at +1.0% (pushing) drift with 26.7mm displacement. At the starting drift (0.01%), the load is still

small because it is the initial time the structure is forced to deform. From the plotted graph,

lateral load and displacement increased as the drift increased. The increment of

displacement for each drift shows that once the force is increased the elongation also

increased.

Figure 7. Hysteresis Loops analysis of the specimen

Stiffness and Ductility

Stiffness can be defined as the extent to which a structure can resist loading with no

significant displacement. For the in-plane response of the 3-storey tunnel form building

system, it showed less flexibility and stiffer behaviour to high loads with low displacement. For

every drift that involved during testing the specimen was contributed to the differences of

elastic stiffness behaviour. Elastic and secant stiffness was depends on structural behave

-100

-80

-60

-40

-20

0

20

40

60

80

-30 -20 -10 0 10 20 30

0.01% Drift 0.1% Drift 0.25% Drift

0.5% Drift 0.75% Drift 1.0% Drift

Load

(KN

)

Displacement (mm)


67

under control displacement or drift had been applied. The tabulated of elastic and secant

stiffness is demonstrated in Table 4 for pushing phase. Based on tabulated data, secant

stiffness found to be low value compare to elastic stiffness because the specimen is under

inelastic regions.

Meanwhile, Table 5 shows the elastic, secant stiffness and ductility for pushing phase of the

specimen. The elastic stiffness value obtained from pulling phase is much higher compared

to pushing phase. This indicated that the 3-storey tunnel form building system is much more

stiffened in pulling phase rather than pushing phase. Same goes to the ductility value from

pulling phase, it is found to be 0.59 higher than pushing phase obtained from 1.0% drift.

Table 4 . Elastic, Secant Stiffness and Ductility for Pushing phase

Drift (%)

Pushing

Displacement Elastic Secant

(mm) stiffness Stiffness Ductility

(kN/mm) (kN/mm)

0.01 0.5 5.54 - 0.08

0.1 2.3 5.69 - 0.41

0.25 5.64 11.03 - 1

0.5 13.68 - 2.18 2.43

0.75 19.84 - 3.14 3.52

1 26.7 - 2.69 4.73

Table 5 . Elastic, Secant Stiffness and Ductility for Pulling phase

Drift (%)

Pulling

Displacement Elastic Secant

(mm) stiffness Stiffness Ductility

(kN/mm) (kN/mm)

0.01 0.1 18.7 - 0.02

0.1 1.8 7.1 - 0.38

0.25 4.78 15.89 - 1

0.5 11.32 - 3.62 2.37

0.75 15.36 - 4.95 3.21

1 23.4 - 3.84 4.89


68

Equivalent Viscous Damping (EVD)

Equivalent viscous damping (EVD) is a measurement of energy dissipated amount during the

load applied to the structure. In this study, the percentage EVD is calculated in 2 separate

loops that recognize first and second cycles. The EVD percentage is obtained from 0.1% drift

until 1.25% drift for both pushing and pulling phase. The calculation of equivalent viscous

damping is formulated in equation (1) as follows :

[(

) (

)] (1)

Where is;

Equivalent Viscous Damping

π Function for circular 3.142 in unit dimensions

ED Energy dissipated within the maximum triangle area

Eso Total Energy within trapezium area

Figure 8 shows the percentage of equivalent viscous damping (EVD) of 3-storey tunnel form

building system. From the graph, the maximum energy absorption comes from the first cycle

with 15.6% of EVD obtained from 0.25% drift and it dropped linearly until 0.5% drift. This

indicated that the amount of energy released from the structure and caused the

appearance of cracks and concrete sealing. But at the same drift (0.5%) the EVD started to

increase until 0.75% drift and stopped at 13.45%. EVD percentages for the second cycle

started at 6.60% at 0.1% drift and increased to7.28% at 0.25% drift. However, at 0.5% drift the

EVD dropped to 12.78% but increased until 1.0% drift with 11.57%. EVD value obtained from

the first cycle is higher than the second cycle. This indicates that the specimen required

much more amount of energy to resist the earthquake loading in the first strike compared to

the second strike.

Figure 8. Equivalent Viscous Damping versus Drift

0

3

6

9

12

15

18

0 0.2 0.4 0.6 0.8 1 1.2

1st cycle

2nd cycle

EV

D (

%)

Drift (%)


69

CONCLUSION

This experimental study is to investigate the seismic performance of a 3-storey double unit

tunnel form building system subjected to in-plane lateral cyclic loading. The experiment was

conducted using load actuator machine within the displacement control. The first crack

started to occur at -0.25% drift with a maximum 24 kN on the wall-slab joint of wall 1 (first

floor). Then the crack continuously occurred until +1.25% drift and induce a diagonal crack.

The crack pattern on each wall surface started to crack at edge of length panel then

propagate until the middle of the wall panel. This behavior of the crack pattern showed that

failure of crack within maximum stress occurred at the edge surface. The crack was started

to propagate when the load and displacement is increased. The crack is also occurred on

the wall 1 and wall 3 rather than wall 2. This means that the most full supported edge will

suffer less displacement compared with the only half supported.

Ultimate lateral load obtained from 1.0% drift with 71.84kN and 26.7mm displacement for

pushing phase. Meanwhile, for the first negative cycle (pulling phase), the maximum loading

was observed to be 89.8kN from 1.0% drift with 23.4mm displacement. It differs 25.6% to each

phase (pushing and pulling) because at this stage the structure become to its original

position after the loading imposed to it. It means that the structure needs 18.4kN to come to

its unloading position. The hysteresis loop pattern can be concluded that the seismic

performance of the experimental prototype building of tunnel form building system is having

the yield loading and displacement at 0.25% drift within 62.26 kN and 5.64 mm respectively.

Based on stiffness analysis, elastic stiffness gives a greater value comparisons with secant

stiffness for almost each drift. This indicated that the tunnel form building is under inelastic

regions.

Meanwhile, the ductility behavior of the specimen is 4.8 which is remaining under 6. It means

that the ductility of this specimen is in the range of good performance of the seismic

response. For the equivalent viscous damping (EVD) analysis, the energy dissipated for the

first cycle is much higher compared to the second cycle. This is because during the first strike

of earthquake (first cycle) the specimen required more energy to resist the lateral loading as

compared to the second strike (second cycle).

Therefore, it can be concluded that tunnel form building system performed well under long

distant earthquake for minor to moderate. The major crack obtained from the ultimate load

is still under allowable crack which is less than 0.3 mm length as mentioned in clause BS8110:

part 1. Therefore, it is recommended that the tunnel form building system should be repaired

and retrofitted since it is under non-collapse behavior.

ACKNOWLEDGEMENTS

The author would like to thank the Research Management Institute (RMI), University Teknologi

MARA and Fundamental Research Grant Scheme (FRGS) for the funding this research work.

Nevertheless, the authors also would like to express their gratitude to the technicians of

Heavy Structures Laboratory, Faculty of Civil Engineering, UiTM for conducting this research

work successfully.


70

REFERENCES

Azlan Adnan, Hendriyawan, Masyhur Irsyam. 2002. The Effect of the Latest Sumatra

Earthquake to Malaysian Peninsular. Journal of civil engineering, Vol. 15 No. 2.

Al-Aghbari, A., Hamzah, S.H., Hamid, N.H. and Rahman, N. 2012. Structural Performance of

two types of Wall Slab Connection Under Out-of-Plane Lateral Cyclic Loading,

Journal of Engineering Science and Technology, Vol. 7, No. 2, pp. 177-194.

Balkaya C. and Kalkan E. 2004. Seismic Vulnerability, Behavior and Design of Tunnel Form

Buildings, Engineering Structures 26(2004), 2081-2099.

British Standard. BS8110-1. 1997. Structural use of concrete-Part 1: Code of practice for design

and construction. BS8110-1:1997.(1997), London, UK, 172.

Garcia, L.E, and Sozen, M.A. 2004. Earthquake Resistant Design of Reinforced Concrete

Building, in Earthquake Engineering from Engineering Seismology to Performance-

Based Engineering book, edited by Yousef Bozorgnia and Vitelmo Bertero, CRC Press,

New York

Hamid, N. H., and Masrom, M. A. 2012. Seismic Performance of Wall-Slab Joints in

Industrialized Building System (IBS) Under Out-Of-Plane Reversible Cyclic Loading,

IACSIT International Journal of Engineering and Technology, Vol. 4, No. 1.

Ionut-ovioui Toma and Gabriela M. Atanasiu. 2010. Modern Trends In Experimental

Earthquake Engineering Research. Buletin of The Polytechnic Institute of IASI,

Technical University “Gheorge Asachi” of Tome LVI (LX), Fasc.

Satpute SG and DB Kulkarni. 2013. Comparative Study of Reinforced Concrete Shear Wall

Analysis in Multi-Storeyed Building With Openings by Nonlinear Methods. International

Journal of Structural and Civil Engineering Research, Vol. 2, No. 3.

Taksiah A. Majid, Shaharudin Shah Zaini, Fadzli Mohd. Nazari, Mohd. Rashwan Arshad and

Izatil Fadhilah Mohd Suhaimi. 2007. Development of Design Response Spectra For

Nothern Peninsular Malaysia Based on UBC 97 Code. The Institution of Engineers

Journal, Vol. 68, No. 4.


71

Review of coastline changes due to erosion at Pantai UMT

W.B. Wan Nik

Department of Maritime Technology, Faculty of Maritime Studies and Marine Science,

Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu

ABSTRACT. Marine ecosystem includes the area at the shoreline is the area which sensitively

reacts with any changes occur around it. The changes might affects either temporarily or

permanently. These changes include alteration in morphology, beach profile and contour.

Coastal development creates hazard which affects the natural environment such as erosion.

Reclamation of sand to form a runway for Sultan Mahmud Airport is an example of coastal

erosion due to man-made product. The aim of this study is to evaluate the changes of the

beach near Universiti Malaysia Terengganu (UMT). This study also provides a few ways to

overcome the problem. The study area was set from Sultan Mahmud Airport to Pantai

Mengabang Gelam which covers the coastline area of 3.4 kilometres. Visual observation was

done to the studied area to see the changes of coastline. It was found that the

development of the runway for Sultan Mahmud Airport has caused severe erosion along this

studied area. There is structural damage along this shoreline and the devastation has

affected socio economy of surrounding resident. This paper reports the erosion process

occurs along the coastline of Tok Jembal and UMT and the method applied to overcome

erosion.

KEYWORDS: erosion, coastal development, rock revetment

Introduction

Malaysia’s coastline is over 4,809 km where over than 1500 km of this coastline experiencing

corrosion. The number has increased up to 2327km presenting of increment in project

number from 47 sites to 74 sites in 2000 [1].

Construction of infrastructures at coastal areas may serve the economic development and

social needs. However the effect on coastal areas should be taken into consideration

because of the natural process interference. Erosion is an example of interference causes by

development of coastal areas. Erosion in Malaysia is in distressing stage where the number of

problem increased over the last 12 years [2].

Therefore, erosion prevention method and shoreline monitoring should be implemented as

an initiative to reduce this disastrous process. The aim of this paper is to show the coastal

area near Universiti Malaysia Terengganu that severely suffers because of the corrosion.

Observation at the coastal area was conducted to visualise the erosion process and

secondary was used to expect the future changes on the shoreline.

Method

Structural observation

Observation was conducted near coastal area of Sultan Mahmud Airport to Mengabang

Gelam which covers the coastline areas of 3.4 km.


72

Result and Discussion

One week survey was conducted at coastal area of UMT on 2011 as shown in Figure 1. It

can be observed that there was no significant change on the beach within 4 days of

surveying and the zone is considering relict although it is near to Tok Jembal coastline. It is

believe that the long shore current carried sediment from erosion site and deposit at coastal

area of UMT thus form a relict zone.

Figure 1 coastline observation on 2011 (12 November 2011 – 21 November 2011)

The shoreline of the coast along Sultan Mahmud Airport to Mengabang Gelam is composed

of sandy materials. The sediments were easily erodible when facing an impact by the wave

and if not well protected. Figure 2 shows the coastal area at Universiti Malaysia Terengganu

where the photo was taken on 2012 and 2013. In the duration of 7 September 2012 to 9

January 2013, a massive change was observed at the coastal area. Student’s activity can

still be conducted on September 2012. However on the January 2013, the coastal area was

severely eroded.

Figure 2 massive changes of coastal area near UMT from September 2012 until January 2013


73

Erosion process mainly divided into two categories namely as natural erosion and human-

induced erosion. Massive changes from September 2012 to January 2013 are a result of

structural development at Sultan Mahmud airport and ironically it causes direct effect to the

coastal area and few depositions at the surrounding area were found.

Figure 3 shows the effect on erosion towards the fisherman community where it can be

observed that the road was extremely damaged while Figure 4 shows severe erosion occur

at coastal area of Tok Jembal.

Figure 3 Extreme damages at the fisherman community

Figure 4 Severe erosion at coastal area of Tok Jembal

Figure 5 shows the rock revetment deployed at the coastline of Sultan Mahmud airport. The

implementation of this method to overcome the problem is suitable because of it consume

lower cost compare to the other method such as beach nourishment. However this method

reduces the aesthetic value and hence affects the tourism industry. Furthermore, there will

be serious erosion at the end of this revetment.


74

Figure 5 Rock revetment installed at coastal area of Sultan Mahmud airport

Conclusion

It was found that structural development along coastline area has caused severe erosion

resulting in cost increment to overcome this problem. an active and progressive strategy

should be considered to conserve the coastline so that sustainable development of resource

at that particular area can be preserved. Therefore, development of coastal area should

come with the systematic effort to preserve coastal area and at the same time it can control

the rate of erosion.

References

A. Chalabi, H. Mohd-Lokman, I. Mohd-Suffian, Masoud Karamali, V. Karthigeyan, M. Masita

(2006), monitoring shoreline change using ikonos im age and aerial photographs: a

case study of Kuala Terengganu area, Malaysia, Proceedings of the ISPRS Commission

VII Symposium

'Remote Sensing: From Pixels to Processes', volume XXXVI Part 7, 1-6

E.C. Lee & R.S. Douglas (2012), Geotextile tubes as submerged dykes for shoreline

management in Malaysia, Geotextiles and geomembranes, 30, 8-15


75

AN OVERVIEW OF WINDSTORM PHENOMENON IN PENANG STATE OF

MALAYSIA

F.A. Wan Chik*, T.A. Majid1,2,

S . N . C h e D e r a m a n 2 , M.K.A. Muhammad2

1Disaster Research Nexus, E n g i n e e r i n g Ca m p us , Universiti Sains Malaysia 14300 Nibong

Tebal, Penang, Malaysia 2School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong

Tebal,Penang, Malaysia.

ABSTRACT. During monsoon season, heavy rain and windstorm prone occurred in micro

scale and affected east coast of Peninsular Malaysia and East Malaysia. Aim of this

conducted pilot study is to review on the occurrence of strong wind and house damaged in

five districts in Penang. Data was collected in four years period from 2010 to 2013 for five

respective districts in Penang which acquired from Land and District Office, thus, all data

were analyzed. Meanwhile, the frequencies of heavy storm occurrence and number of

houses damaged have been obtained. Data comparison between every district in terms of

occurrence in month and year and number of damages were established from the plotted

graph. From the graph, the highest frequency of windstorm occurrence was found at

Northern Penang (SPU), with 538 cases was reported, and followed by Southern Penang

(SPS), with 50 cases, Central Penang (SPT), with 29 cases, South West Penang (BD), with 3

cases and the lowest occurrence at North East Penang (TL), with 2 cases. The highest

number of houses damaged was hampered in year 2012 at Northern Penang (SPU) with 243

number of houses, while, the least number of houses damaged occurred in year 2011at

North East Penang (TL) by only one house damage. The trend number of occurrence and

damaged also observed step up yearly due to the climate change and global warming

tendency. The important factor that may contribute to climate change is urbanization. This

study shows that windstorm is a phenomenon and must be considered in Malaysia. It is

important to note that a rise in severe windstorm events, thus, increase the damages and

losses and also human life.

KEYWORDS: Wind storm occurrence, frequencies, number of house damaged.

INTRODUCTION

Malaysia is a country with a tropical climate; whereby, the coastal plains which averaging

28°C, the inland and mountain averaging 26°C and the higher mountain regions

temperature at 23°C. Heavy rain and windstorm which take place during monsoon season

probably affected east coast and east of Malaysia. Malaysia Meteorological Department

(MMD) reported that windstorms are most likely to occur in the inter monsoon period in April

to May and October to November. According to Yusoff, (2005), occurrence of windstorm in

our country is in micro scale, with small size and short duration between 15 to 30 minutes. In

accordance, these passive conditions produce hail, heavy rain, frequent lightning and

strong gusty winds (Holmes, 2001). Severe windstorm associated with hail and wind gusts

may result in strong wind and can caused severe damages to extensive area. Low rise non-

engineered structure is very prone to the destruction due to strong wind. It was stated by

Majid et.al, (2012) that most of the house damage occurs in northern region on Peninsular

Malaysia. Aim of this conducted pilot study is to review on the occurrence of strong winds

and house damaged in five districts in Penang state from 2010 to 2013. Windstorms in

Malaysia must not be negligible since the occurrence has initiated damage and losses to

structures and human life and fatality.


76

METHODOLOGY

Penang state is located in the northern region of Malaysia; the island portion is separated by

Straits of Malacca adjoining the mainland. There are five districts; two districts in island

portion and balance of three districts are situated in the mainland as shown in Figure 1. For

North East Penang (TL) and South West Penang (BD) are located in island meanwhile,

Northern Penang (SPU), Central Penang (SPT) and Southern Penang (SPS) are located in the

mainland accordingly.All data on occurrence of windstorm and house damaged were

collected from Land and District Office in Penang, were gathered and tabulated. Graph for

number of occurrence and number of houses damaged were plotted with reference to

month, year and districts. The discussions were based on the results obtained.

Figure 1: Districts in Penang state

RESULTS AND DISCUSSION.

Windstorm occurrences

The graph was plotted to determine the frequencies of windstorm occurrence in four years

with reference to month. Figure 2(a) shows the data for monthly windstorm occurrence for

Northern Penang (SPU) in 2010 to 2013. In four years data period, it shows that the highest

occurrence of windstorm was in March by 14 cases. Meanwhile the lowest windstorm event

was recorded in December with only two cases during the same data period. The result

shows the highest occurrence is due to the annual contribution of windstorm event. For

Central Penang (SPT), the frequencies of windstorm occurrence were shown in Figure 2(b)

for only three years data period. The graph denotes that there is no data recorded in 2010

due to some circumstances. Similar to Northern Penang (SPU), the highest windstorm

occurrence for Central Penang (SPT) occurred in March by 8 cases. For the month of May,

July, August September and October only once wind storm occurrence in 2012 strikes in

three years period. The graph trend also indicates that windstorm increase slightly in that

particular month. No wind storm occurrence was recorded in June, November and

December for Central Penang (SPT) during three years data period.

Figure 2(c) depicts the monthly windstorm occurrence for Southern Penang (SPS) in 2010 to

2013. The graph trend shows the number of occurrence increases with the increase of

month. The highest peak was observed in May which contributes from four years recorded

data simultaneously windstorm occurrence in the same month. In June, the graph start

decreasing whereby, 3 cases were recorded in 2011, 2012 and 2013 accordingly. However,

windstorm event stabilized for two months; July and August by 5 cases. Similar goes to

September and December by 2 cases. For October, windstorm only recorded in 2012 by 3

cases.

Figure 2(d) represents the monthly windstorm occurrence for North East Penang (TL) in 2010

North East

Penang South West

Penang

Northern Penang

Central Penang

Southern Penang


77

to 2013. The slightest windstorm occurred at North East Penang (TL) as compared to other

four districts. In conjunction to the above, there is no windstorm event recorded in 2012 and

2013. Data monitoring for year 2013 is noted until July. However, only 2 cases were recorded

at North East Penang (TL) which is in March 2010 and May 2011. Figure 2(e) shows monthly

windstorm occurrence for South East Penang (BD) with regards to the data collections from

2010 to 2013. For 2010, there is no data available for windstorm. In 2011, windstorm only

occurred once in December, meanwhile, for 2012 it shows that windstorm occurred in June.

The same goes to 2013, windstorm only recorded in March by one case.

From the graph, the number of windstorm occurs in five districts in Penang within 4 years

time period; it shows that the highest number of windstorm occurs in March for SPU and SPT

while, in May for SPS. According to Malaysian Meteorological Department (MMD),

windstorm can occur throughout the year but most likely to happen in the inter-monsoon

periods, namely April to May and October to November. Over land, windstorm frequently

develop in the afternoon and evening hours while over the sea, windstorm is more frequent

at night.

(a) Central Penang (SPU) (b) Northern Penang (SPT)

(c) Southern Penang (SPS) (d) North East Penang (TL)


78

(e)South East Penang (BD)

Figure 2: Windstorm occurrence in five districts of Penang State in 2010 to 2013

Meanwhile, Figure 3 shows the frequency of windstorm occurred in Penang state from 2010

to 2013. From the graph, highest number of windstorm occurred at Northern Penang (SPU),

with 538 cases, followed by Southern Penang (SPS), with 50 cases, Central Penang (SPT), 29

cases, South West Penang (BD) with three cases and the lowest number of windstorm

occurrence is at North East Penang (TL), with two cases during 2010 to 2013.

Figure 3: Frequency of windstorm occurred in Penang state from 2010 to 2013

Damaged of Houses

Graph illustrated in Figure 4 represent data for the number of houses damaged yearly with

regards to five districts in Penang state. In 2010, windstorm has affected three districts which

are Northern Penang (SPU), Southern Penang (SPS) and North East Penang (TL) respectively.

The highest number of house damaged in North East Penang (TL) is 136 houses, followed by

Northern Penang (SPU), 72 houses and Southern Penang (SPS) with 29 houses reported. Four

out of five districts struck by the windstorm in 2011 namely, Northern Penang (SPU), Central

Penang (SPT), Southern Penang (SPS) and South West Penang (BD). It was recorded that the

total number of houses damaged at Northern Penang (SPU) is 193, 77 houses in Southern

Penang (SPS), 72 houses in South West Penang (BD), 29 houses in Central Penang (SPT) and

one house damaged in North East Penang (TL). Further, the graph shows in year 2012 was

the worst year affected by windstorm, total figure out 400 houses damaged. Northern

Penang (SPU) was badly affected by windstorm whereby 243 number of houses damaged,

Southern Penang (SPS) by 96 houses, Central Penang (SPT) by 32 houses and South West

Penang (BD) by 29 houses. No house observed in North East Penang (TL) involves in the


79

windstorm occurrence. Meanwhile, there are 100 numbers of houses damaged in 2013 and

approximately, house damage may rise up until year end. Previous data of windstorm

occurrence shows increasing trend yearly.This result is also in line with finding by Majid, et.al,

(2012) stated that number of damages are constantly increase year by year with rapid

growth of development.It was recorded that 29 numbers of occurrence observed in 2010,

43 occurrences in 2011 rise by (48.28%) from previous year, 56 occurrences in 2012 by

(30.23%), thus, in 2013 there was 29 occurrences recorded until month of August. Tendency

for wind storm occurrence to hike up for year 2013 most probably is due to the inter-

monsoon season during October to November.

Figure 4: Yearly number of houses damaged with regards to five districts in Penang state

Meanwhile, Figure 5 summarizes recent trend windstorm occurrence which clearly indicates

the tendency of houses damaged increase yearly throughout four years data period. In

year 2013 shows decreasing trend because the data recorded were cut off by August.

House damaged cases mainly affected the low rise buildings. Majority low rise buildings

among the building structures in Malaysia face the great impact during the event. It was

identified that 80% of the cases caused damaged to the roofing systems due to the

thunderstorm in Peninsular Malaysia. Damage breakdown shows that 47% damage in steel

sheet roofing, 30% damage on trusses system, 13% damage on roof tiles and 20% for other

related damages stated by Majid, et. al (2012).Windstorm occurrence in Malaysia must be

considered. Building codes and guidelines in Malaysia need to be revised very carefully.

Figure 5: Windstorm summary in Penang state.


80

CONCLUSION

This study shows that windstorm is a phenomenon that should be taken seriously for many

reasons in Malaysia. It is important to note that a rise in severe windstorm events, thus,

increase the damages and losses and also human life. Damages, losses and social problems

are casualties that could create by this natural disaster. All natural disasters including those

related to wind have enormous socio-economic implications in terms of the sustainability of

the human habitat and built environment. Although Malaysia is not in cyclone prone region,

a good awareness should be taken to reduce the loss due to windstorm and loss of life.

REFERENCES

Yusoff A. (2005), “A study on the characteristics of thunderstorm at Telekom Malaysia

communication center, Seberang Jaya, Penang”., MSc Dissertation,School of Civil

Engineering, UniversitiSains Malaysia.

Holmes J. D. (2001). “Wind Loading of Structures”. Spon Press, Taylor & Francis Group, New

York.

Majid, T.A, NoramI.Ramli, Ali M.I., Syamsul, M.H.Saad, Malaysia Country Report 2012: Wind

Related Disaster Risk Reduction and Wind Environmental Issues.


81

THE STABILITY OF TEMBURUNG FORMATION IN BEAUFORT AREA, SABAH

Ismail Abd Rahim

Natural Disasters Research Unit, School of Sciences & Technology,

Universiti Malaysia Sabah, Jalan UMS

88400 Kota Kinabalu, Sabah, Malaysia

Phone: 088 320000 (5734/5999)

Fax: 088 435324

[email protected]

ABSTRACT. The aim of this paper is to determine the stability and to propose preliminary rock

cut slope protection and stabilization measures for Oligocene to Late Eocene Temburung

Formation in Beaufort, Sabah. Six (6) slopes were selected for this study. Geological mapping,

discontinuity survey, kinematic analysis and prescriptive measure were used in this study.

Results of this study conclude that the modes of failures are wedge, planar, circular and

complex. Gunite, soil nail, weep hole, slope reprofiling, terrace, drainage and retaining

structure are proposed stabilization and protection measures for the slope in the study area.

KEYWORDS: Temburung formation, Beaufort, mitigation measure, slope stability, mode of

failure

INTRODUCTION

The development of instabilities in rock cut slope is a serious problem with a significant

economic and social impact. Catastrophic failures of rock cut can result in property

damage, injury and even death.

The development of instabilities depends on the combination of the rock mass

characteristics (strength, lithology, structure and degree of weathering), the preservation of

the slope and how water enters into the system, the relationship between the rainfall-runoff

and the groundwater. Combinations of these factors contribute to the large number of

accidents during and after construction work, as well as loss of both material resources and

lives (Uribe-Etxebarria et al., 2005).

In Beaufort area, especially in Temburung formation this situation appear related to rock

mass characteristic and its abundant rainfall. Intense jointing and shearing and thick shale

layers were characterized the rock mass of the Temburung formation to small (1cm3 – 1m3)

polygonal block shape, irregular block type and low strength.

The occurrence of slope failures in km 130.1 and 112 on 9 April 2013 (Photograph1A and 1B)

and km 123.8 of Beaufort-Tenom railway on 2008 (Photograph 1C) with 1 mortality has

becomes an issue for this study.

This study was conducted in Temburung formation only because the slope failures was

happened in Temburung formation. There are six (6) rock cut slopes have been evaluated

and identified as slope 1, 2, 3, 4, 5 and 6. The locations of rock cut slopes for this study are

shown in Figure 1.



82

Photograph 1 Slope failures. A - km 130.1 (2013); B – km 112 (2013); C – km 123.8 (2008).

METHODOLOGY

Geological mapping, discontinuity survey and kinematics analysis have been used to

evaluate the stability of slope in study area. Geological mapping includes lithological and

structural identification, measurement and interpretation. For discontinuity survey, scanline

method was conducted by following ISRM (1981) procedure. DIPS 5.0 software package

(Rocscience, 2009) has been used to identify the discontinuity set or average orientations of

discontinuity sets.

Evaluation of rock slope stability was performed by kinematic analyses (Markland, 1972).

Kinematic refers to the motion of rock mass bodies without reference to the forces that

cause them to move (Goodman, 1989). A kinematic analysis is very useful to investigate

possible mode of failure of rock masses which contain discontinuities (Jeongi-gi Um &

Kulatilake, 2001).

In the Kinematic analysis, it is assumed that the friction angle (Ø) for the discontinuity planes is

about 30 (Kliche, 1999; Hoek & Bray, 1981). This value is assumed to represents average

friction angle for the slope material. However, it is noted that this value may be decreased

down to as low as 27 in the presence of seepage along the discontinuity planes, or

increased up to 35 in dry, very hard and rough discontinuity surface.

The slope stabilization and mitigation measures were determined by prescriptive measures

(Yu et al., 2005) and using conventional engineering practices.

GEOLOGY

The study area is underlain by the Crocker and Temburong Formations, which is inter-

fingering between others as well as alluvium deposits with the age of Pleistocene and Recent

(Figure 1). These two formations are part of turbidite deposit.


83

Figure 1 General geological map and slope locations of the Beaufort-Tenom railway area

(modified from Wilson & Wong, 1954; Yin, 1985).

The Crocker Formation is Late Eocene to Early Miocene ages and composed of a few types

of Lithology such as thick sandstone unit, interbedded sandstone and shale unit and thick

shale unit. The dominant north-south strike of the Crocker Formation gives rise to a series of

elongated parallel ridges. The major structural pattern in this area is dominated by thrust

faults trending northeast-southeast with minor folds system plunging to northeast (Wilson &

Wong, 1964).

The Temburung formation deposited by the age range from Oligocene to Early Miocene

(Sanudin & Baba, 2007). The Temburong Formation slightly deference from Crocker

Formation by its lithological unit, it composed of interbedded thick shale and/without thin

siltstone unit (Photograph 2A), shale thicker than sandstone interbedded unit (Photograph

2B) and sandstone thicker than shale interbedded unit (Photograph 2C).

The Pleistocene alluvial terrace is composed of coarse gravel in most outcrops. The Recent

alluviums is observed along the riverside and flood-plain area.

Photograph 2 Rock unit. A – thick shale and/without thin siltstone unit; B - shale

thicker than sandstone interbedded; C - sandstone thicker than shale unit.


84

RESULTS

The six (6) slopes, rock mass characterization and slope instability in the study area are shown

in Photograph 3 and Table 2. The slopes are showing varied lithological units i.e. thick shale

and/without thin siltstone unit, shale thicker than sandstone interbedded unit and sandstone

thicker than shale unit.

Photograph 3 Slopes. A – slope 1; B – slope 2; C – slope 3; D – slope 4; E – slope 5; F – slope 6.

Table 2 Slope, rock mass characteristic and instability.

Slope Characteristic Instability

Observation

1 Sandstone thicker than shale unit. Highly jointed and faulted. No

seepage. Low discontinuity persistence. Small block size and

irregular block shape.

Rock block, wedge

plane

2 Shale thicker than sandstone unit. Highly jointed and sheared. No



Rock block, wedge

plane, debris

deposit

3 Sandstone thicker than shale unit. Highly jointed and faulted.

Seasonal seepage. Low discontinuity persistence. Small block size

and irregular block shape.

Rock block, wedge

plane, debris

deposit

4 Thick shale and thin siltstone unit. Highly jointed, sheared and

faulted and sheared. Water seepage occurs. Low discontinuity

persistence. Very small block size and irregular block shape. Soil

like.

Circular plane,

debris deposit


85

5 Shale thicker than sandstone unit. Highly jointed and faulted.

Seasonal seepage. Low discontinuity persistence. Very small block

size and irregular block shape.

Wedge plane,

debris deposit

6 Sandstone thicker than shale unit. Highly jointed, sheared and

faulted. Seepage occurs. Low discontinuity persistence. Small block


Circular plane,

debris deposit

(colluvium deposit)

The rock mass is generally highly jointed, sheared and faulted. Seepage occurs in the slope

represented by moderate to thick shale beds. The persistence of discontinuity is low unless

the bedding planes. The block size is small for sandstone beds but very small for thin

sandstone and thick shale beds. The block shape is tabular to irregular. The highly weathered

thick shale unit shows the rock mass as soil like and weak.

Observed instability features on the slope face are failure planes [circular (Photograph 4A),

wedge (Photograph 4B), and complex failures (Photograph 4C)], debris deposits and rock

blocks. Results of the Markland test are shown in Figure 2 and Table 3. The potential modes of

failures from the test are wedge, circular, planar and complex failures.

Photograph 4 Slope failure. A – circular failure; B – wedge failure; C – complex failure.

Figure 2 Markland test for slope 1 to slope 6.


86

Table 3 Slope, rock mass characteristic and instability.

Slope Characteristic Instability

Observation

1 Sandstone thicker than shale unit. Highly jointed and faulted. No



Rock block, wedge

plane

2 Shale thicker than sandstone unit. Highly jointed and sheared. No



Rock block, wedge

plane, debris

deposit

3 Sandstone thicker than shale unit. Highly jointed and faulted.

Seasonal seepage. Low discontinuity persistence. Small block size

and irregular block shape.

Rock block, wedge

plane, debris

deposit

4 Thick shale and thin siltstone unit. Highly jointed, sheared and

faulted and sheared. Water seepage occurs. Low discontinuity

persistence. Very small block size and irregular block shape. Soil

like.

Circular plane,

debris deposit

5 Shale thicker than sandstone unit. Highly jointed and faulted.

Seasonal seepage. Low discontinuity persistence. Very small block


Wedge plane,

debris deposit

6 Sandstone thicker than shale unit. Highly jointed, sheared and

faulted. Seepage occurs. Low discontinuity persistence. Small block


Circular plane,

debris deposit

(colluvium deposit)

DISCUSSION

Six (6) rock cut slopes of the Temburung Formation were analyzed by kinematic analysis

along Beaufort-Tenom railway. The Temburung Formation has varies engineering geological

properties and two to four discontinuities sets including bedding planes or joints.

According to the Markland’s test, a plane failure is likely to occur when a discontinuity dips in

the same direction (within 20o) as the slope face, at an angle gentler than the slope angle

but greater than the friction angle along the failure plane. A wedge failure may occur when

the line of intersection of two discontinuities, forming the wedge-shaped block, plunges in

the same direction as the slope face and the plunge angle is less than the slope angle but

greater than the friction angle along the planes of failure. A toppling failure may result when

a steeply dipping discontinuity is parallel to the slope face (within 10o) and dips into it (Hoek

& Bray, 1981; Ismail Abd Rahim, 2011).

Combination of more than two wedge failures with other failure such as planar, toppling or

circular will forming complex failure. Intersection of J4 with J2, J1 with B and J1 with J2 in slope

1, 5 and 6 contributes to the formation of wedge failures, respectively. Intersection of J4 with

J1, J4 with J2 and J1 and J2 in slope 2 but more than 20o difference of intersection lines with

dip direction of slope faces has forming partly potential wedge failure. Combination of

planar and wedge failures in slope 5 contribute to the formation of complex failure as

occurred in 2008. Possibilities of wedge, planar and circular failures in slope 3 have made

these slopes partly potential for complex failure.


87

Application of geological characteristics, properties of the rock mass and mode of failures to

proposed remedial measures for rock cut slopes was used widely (Amin, 1999; Kentil & Topal,

2004; Ismail Abd Rahim et al., 2010). Summary of the slope protection and stabilization

measures for the study area are shown in Table 4.

Slope reprofiling is recommended for slope 3. All slope needs to be install with subsurface

drainage but guniting. Slopes 6 needs to be provided by surface drainage system and

soilnail for slope 2, 3, 4, 5 and 6. Terrace must be made in slope 6 and retaining structures

need to be built in slope 5 and 6.

Table 4 Slope protection and stabilization measures.

Slope Slope

reprofiling Gunite

Subsurface

drainage Drainage

Soil

nail Terrace

Retaining

structure

1 / /

2 / / /

3 / / / /

4 / / /

5 / / / /

6 / / / / / /

CONCLUSION

Conclusions of this study are;

1. The potential modes are wedge, planar, circular and complex failures.

2. Most of the rock cut slopes are unstable unless slope 1.

3. Slope refrofiling, guniting, subsurface drainage, drainage, soil nailing, terrace and retaining

structure are proposed mitigation and stabilization measures.

REFERENCES

Amin, A. A. 1999. Geologic hazard along part of Al-sayl-Alkabeir Al-Jammun road in Saudi

Arabia. Environmental Geology, 39 (1): 20-24.

Goodman, R. E. 1989. Introduction to Rock Mechanics. 2nd ed. John Wiley & Son, New York.

Hoek, E. & Bray, J. W. 1981. Rock Slope Engineering. 3rd ed. Institution of Mining and

Metallurgy, London, 359pp.

Ismail Abd Rahim, Sanudin Tahir, Baba Musta, & Shariff A. K. Omang. 2010. Slope Stability

Evaluation of Selected Rock Cut Slope of Crocker Formation in Kota Kinabalu, Sabah.

Proceeding of the 3rd Southeast Asian Natural Resources and Environmental

Management (SANREM 2010), 3-5 August 2010, Promenade Hotel, Kota Kinabalu,

Sabah.


88

Ismail Abd Rahim. 2011. Rock mass classification system of the Crocker Formation in Kota

Kinabalu for rock slope engineering purposes, Sabah. PhD Thesis. Universiti Malaysia

Sabah, Kota Kinabalu.

Ismail Abd. Rahim, Sanudin Haji Tahir, Baba Musta, & Rodeano Roslee. 2006. Slope Stability

Assessment of the Crocker Formation in the Telipok, Sabah. Proceeding of the

Southeast Asian Natural Resources and Environmental Management Conference

(SANREM 2006).21-22 November 2006, Le Meridian Hotel, Kota Kinabalu.

ISRM, 1981. Rock Characterization, Testing and Monitoring. In: Brown, E.T. (Ed.). International

Society for Rock Mechanics (ISRM) Suggested Methods. Pergamon, Oxford. 211 pp.

Jeongi-gi Um & Kulatilake, P. H. S. W. 2001. Kinematic and Block Theory Analysis for Shiplock

Slope of the Three Gorges Dam Site in China. Geotechnical and Geological

Engineering, 19: 21-42.

Kentil, B. & Topal, T. 2004. Evaluation on rock excavatability and slope stability along a

segment of motorway, Pozanti, Turkey. Environmental Geology, 46: 83-95.

Kliche, C.A., 1999. Rock slope stability. Society for Mining, Metallurgy and Exploration, Inc.

Markland, J. T. 1972. A Useful Technique for Estimating the Stability of Rock Slopes when the

Rigid Wedge Slide Type of Failure is Expected. Imperial College Rock Mechanics

Research reprint, n. 19.

Rocscience. 2009. Dips 5.0 Graphical & Statistical Analysis of Orientation Data©2009.

Rocscience Inc. http://www.rocscience.com.

Sanudin Tahir and Baba Musta, 2007. Pengenalan kepada stratigrafi. University Malaysia

Sabah, Kota Kinabalu, Sabah.

Uribe-Etxebarria G, Morales T, Uriarte JA, Ibarra V. 2005. Rock Cut Stability Assessment in

Mountainous Regions. Environmental Geology, 48 (8): 1002–1013.

Wilson, R.A.M. and Wong, N.P.Y., 1960. The geology and mineral resources of the Labuan and

Padas Valley area, Sabah, Malaysia. Geol. Surv. Malaysia Mem. 17.

Yu, Y. F., Siu, C. K. & Pun, W. K. 2005. Guidelines on the use of prescriptive measures for rock

cut slope. Geo Report No. 161. Geotechnical Engineering Office, Hong Kong.

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